Last updated: Monday, 29 May, 2017 9:28 AM
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How to successfully grow coriander in a vegetable garden
Coriander is an annual herb with feathery leaves that are used in salads and oriental dishes. For the best results, choose a suitable variety, such as ‘Cilantro’. In April, select a warm, sunny spot with a fertile, well-drained soil and sow the seeds thinly in ½in-deep drills. If you want a succession of leaves, sow a second batch in May. Start harvesting the young leaves when the plants are 6in tall. Coriander can also be grown for its aromatic seeds. Try the ‘Moroccan’ variety and, after sowing outdoors in mid-spring, thin the seedlings to 10in apart. The seeds will ripen in August, following a display of pretty white and pink-tinged flowers.
How to grow celeriac
This vegetable has a similar taste to celery and, as well as having a range of culinary uses, is quite easy to grow. Choose a reliable variety, such as ‘Monarch’, and sow the seeds in trays during mid-March: place in a heated propagator at a temperature of 18C. Once the seedlings are large enough to handle, prick them out individually into 3in pots and keep in a warm greenhouse.
In late May, the young plants should be hardened off in a cold frame for a few days before planting in a sunny spot and a fertile, moist but well-drained soil. Space them 12in apart and ensure the crowns are at soil level.
During the summer, keep the plants well watered, feed occasionally and remove any sideshoots or decaying leaves, as this ensures smoother, swollen stems. Lift the celeriac from October onwards; use immediately, or trim off the leaves and roots and store in boxes of sand in a cool, dry and frost-free shed.
Throwing in the trowel
Digging over your patch could do more harm than good. Helen Glazeley meets the experts who say we should down spades
At Green, the Garden for Research, Experiential Education and Nutrition, in Stroud, Gloucestershire, three charities are reassessing centuries of practice by examining the effect of digging on nutrient levels in crops.
Matthew Adams, director of the charity the Good Gardeners Association (GGA), says: "There is constant discussion between the Food Standards Agency and the Soil Association as to whether organic is better or not. But the organic sector is concerned with what is not added to the system - chemicals. Just because something is organic, it doesn't guarantee its mineral and vitamin content. It's time to look beyond organic."
And, for the GGA, which has promoted no-dig gardening for 40 years, looking "beyond organic" means starting at ground level. The theory behind the research is that digging disrupts the relationship between soil micro-organisms and plants. This then reduces the flow of nutrients between them, resulting in lower levels of minerals reaching your vegetables.
"In a teaspoon of good soil, there can be six million bacteria, thousands of protozoa and fungi and hundreds of nematodes," says Adams. "When organisms live in balance, soil structure is enhanced and the flow of nutrients increased. When a plant is put into disturbed or dug-up soil, it's harder for it to obtain what it needs."
In the four-year experiment, carrots, potatoes, leeks and spinach are being grown on three plots. Each receives the same amount of compost, but one is single-dug (turned over every year to one spade-depth), one double-dug (turned over to two spade-depths) and the third is not dug at all. On the no-dig plot, compost is spread on the surface in autumn, leaving worms and other organisms to incorporate it into the earth at their own pace.
Each year, the resulting crops are sent to Surrey University to be analysed for 22 minerals. "We chose minerals rather than vitamins because minerals are found in the soil, while vitamins are not," explains Adams.
Among the micro-organisms under examination, special attention is paid to mycorrhiza, the invisible fungal network that penetrates plant roots and allows them better access to nutrients, while also conferring a degree of drought and pest resistance. "Modern gardening methods destroy mycorrhiza by turning its world upside down, drying it out and ripping it apart," says Adams. "Adding chemicals makes this worse."
As mycorrhiza grows only 15-20 cm (6-8in) per year, annual digging never allows it to become properly established.
Adams won't divulge which plots to date have produced the most nutritious vegetables, but admits that there have been some surprises. One is that although Green has been organic for years and produces vegetables with a high nutritional value, there has been as much as a two-fold difference in the mineral levels of potatoes from different plots.
Another surprise is the significance of micro-organisms, rather than mineral levels, in predicting the nutrient levels in the vegetables. "Soil biology provides a more accurate prediction for nutrient uptake than soil chemistry," says Adams.
This research comes at a time when concerns are growing over the nutritional value of our food. Comparisons of vegetables grown in 1991 with those grown in 1940 indicate that mineral content has diminished. Carrots, for example, contain 75 per cent less magnesium and 48 per cent less calcium. Such changes raise worries for our long-term health, and understanding the way vegetables obtain their nutrients is a step towards addressing the problem.
"This research should give some interesting insights into how one should handle the soil," he says. "In my experience, some crops benefit more from one method than another. This could clarify what benefits which.
"Double-digging breaks down the soil and activates it, releasing what's there. No-dig doesn't activate anything but retains what's there. My personal feeling is that perennial crops probably benefit from no-dig, whereas deep roots will benefit more from the soil being dug, so releasing nutrients."
The results are due in 2009. Perhaps then we gardeners will be able to stare out of the window with a clear conscience all winter.
Grow your own meals
It’s time to start planning for a bumper harvest. Tom Petherick shows you which are the best vegetables to sow (mid February)
There are few more satisfactory results of toil in the garden than bumper yields of home-grown organic vegetables. That first dish of new potatoes and baby broad beans is one of the high-lights of the summer.
Prepare the ground
The distinctive flavour of mint is unmistakable. From toothpaste to tea, mint has so many uses that it’s hard to imagine life without it. The good news is there are few easier plants to grow. A sunny spot suits it perfectly and few pets and diseases ever attack. The only problem with mint is that it’s very vigorous. If left unrestrained it will soon make an enormous clump, and if you try to dig it up it can resprout from the tiniest scrap of root. The simple way to avoid this problem is to grow it in a pot using a loam-based compost. Once the plant grows too large for its container, simply take it out and cut it into a more manageable sized chunk using an old kitchen knife. Replant the new piece – it must have roots and shoots – and throw away the excess.
TAKING ROOT CUTTINGS
FLAVOUR-FILLED MINTS TO GROW
Bowles’ mint M. x villosa var. alopecuroides)
Pineapple mint (M. suaveolens ‘Variegata’)
BASIL – POTTED HISTORY
We know it as a humble herb but basil has a long and interesting history. In the past it was held in such high esteem that its botanical name, Ocimum basilicum comes from the Greek ‘basilikan' meaning ‘royal' and it was sacred to both the Haitian goddess of love, Erzulie, and in India, the god Vishnu.
Over the years the herb has been associated with death, medicine and fertility. Nicholas Culpeper, the 17th century English herbalist, recommended basil as an antidote to snake venom and Medieval monks used it as an (unsuccessful) cure for plague, adding the fragrant herb to chartreuse.
On a romantic note, if a young girl put basil on her windowsill it meant she was on the lookout for a suitor and in some countries it was believed a man would fall in love with a woman from whom he accepted some basil as a gift.
And a partner was not all basil could attract. Having a sprig in your pocket was believed to bring wealth in days gone by. Make sure your basil flourishes by following the advice of an old wives' take which says shouting and cursing the basil while planting it will help it grow!
But the strangest basil story of all belongs to the Romans who believed pounded basil leaves left under a rock would breed scorpions!
Which type of basil has the best flavour and how do I grow it in the garden?
There are two common types of basil that are grown for their aromatic foliage: Ocimum basilicum (sweet basil) and Ocimum minimum (Greek bush basil). Sweet basil has large, shiny leaves with white flowers and reaches about 24in in height. Bush basil is smaller and has tiny, pale green foliage. Both are equally delicious.
The easiest way to grow basil is from seed in spring. Fill a tray with compost and scatter the seed on top, before covering with ½in of earth. Leave to germinate on a warm windowsill and, when the seedlings are large enough to handle, prick out individually into 3in containers.
Basil should be treated as a tender annual, so plant in a sunny spot outdoors (or in a container) during late May — pinch out the shoot tips and flowers regularly to encourage fresh growth, and keep the soil moist.
Basil needs light and warmth, but with a midsummer sowing and a sunny windowsill you can get some winter leaves.
When to start dwarf French beans in pots
Dwarf French beans are tender plants and, in areas prone to heavy frosts, should be sown under cover in mid-April. Choose a suitable variety, such as ‘Atlanta’ that has flat pods, or ‘Ferrari’ for its slim and fleshy pods, and sow the seeds individually (2in deep) in 3in pots — leave them to germinate in a warm greenhouse.
The seedlings can be planted (9in apart) in a sheltered, sunny spot with a fertile, well-drained soil in late May or early June. During the growing season, keep the ground moist, especially in dry spells, remove all weeds and harvest the beans in midsummer. Alternatively, the seeds can be sown outdoors (at monthly intervals) from early May to early July — cover the seedlings with fleece if a late frost is forecast. Dwarf French bean seeds are available from Mr Fothergills (0845 166 2511, www.fothergills.co.uk).top of page
Is it possible to grow miniature runner beans?
There are some dwarf runner bean varieties and these are ideal for growing in containers on the terrace. Try ‘Hestia’ for its attractive red and white flowers and long, slim pods; or the early-cropping ‘Hammonds Dwarf Scarlet’, which has red blooms — both reach about 24in-30in tall. In mid-April, sow the seeds (2in deep) individually in 4in pots and leave to germinate in a cool, but frost-free, greenhouse. Once the seedlings have established a good root system, transfer them into 15in containers (five plants per pot). In early June, the containers can be placed outdoors — a sheltered, sunny spot is essential. During the growing season, keep the plants well watered, especially in dry weather, and provide support if they start to flop over. The beans can be harvested throughout the summer. Dwarf runner bean seeds are available from Simpson’s Seeds (01985 845 004, www.simpsonsseeds.co.uk).
GARDENING: A FEAST OF BEANS
Think beyond the green: beans also come in yellow and purple, in all shapes and sizes, some needle-thin and others fat and juicy. And now is the time to sow them.
Borlotti, the Italian version of the common French bean and an essential ingredient in the soup pasta e fagioli, has beautiful pale pink skin streaked with maroon. Or try haricot, a small white bean that cooks to a melting tenderness, absorbing the flavour of other ingredients. The tough outer pod of both these varieties means they do not fatten and mature until mid-autumn, making them a useful vegetable to extend the season.
Of the climbing French beans, ‘Blue Lake' is an excellent pencil-pod variety (ie, thin), ‘Cosse Violette' is a prolific cropper with purple pods and ‘Eva' is good for early cropping. Dwarf French beans include ‘Golden Teepee', which produces heavy clusters of sweet, golden pods.
‘Royalty' has a dark purple pod with a good yield, ‘Borlotti Stregonta' is ideal for freezing and ‘Rob Roy' produces a mottled purple pod that looks amazing against the acid green leaves. ‘White Soissons' is an old haricot variety with large white pods.
Beans need a light and well-drained soil, rich in organic matter. Add compost after you have forked over the ground and rake it flat.
All these beans are frost-tender, so sow in pots, two to a 9cm pot, and keep under glass or on a sunny windowsill until they are ready to be planted out. They should not go in the ground until the end of May and will take about four weeks to push through and become sturdy.
If you have no room indoors, sow directly in the soil at the end of May. Push each bean into the ground 5cm deep, with 10cm between plants and the rows 45cm apart. Repeat the sowing every two weeks until mid-July.
Keep them weed-free and water thoroughly in dry spells. Dwarf varieties need no support but climbers should be supported on 3m bamboo canes joined together in a wigwam shape.
Pick climbing and dwarf French beans regularly to stimulate production, leaving borlotti and haricot beans to ripen on the plant.
When the pods of the borlotti and haricot turn yellow, usually around mid-autumn, pull the entire plant out of the ground and leave it on newspaper to turn brittle. Pod the beans and use immediately or freeze. Alternatively, dry and store them in jars.
May 02, 2004
How to ensure runner beans will produce plenty of pods.
Runner beans only produce a heavy crop of pods when the flowers have been pollinated by bees and other flying insects, so they should be planted in a warm, sheltered spot to encourage insects to visit the blooms regularly. Bees seem to prefer the white-flowered varieties rather than the traditional red-flowered ones, so if cropping has been poor in the past, try the varieties “White Lady” or “White Emergo”.
A lack of moisture around the roots can often cause a poor flower “set” and a lack of beans. To counter this, the plants should be well watered and mulched when planting outside (do this after the risk of frost has passed) and don't allow the soil to dry out, especially in early summer.
Red cabbage is gaining popularity. It doesn’t stand up to frost and the summer-autumn variety ‘Ruby Ball’ (pictured) is harvested in October. To keep the red colour when cooking, add vinegar to the water.
The compact, dark red variety ‘Red Drumhead’ is ideal for small gardens or containers, while ‘Red Jewel’ is popular as it lasts well in the ground and keeps when stored.
Savoy cabbages have crisp, crinkly green leaves (‘Ormskirk’ pictured) and are ready from September until March. For early winter choose a frost-hardy variety such as ‘January King 3’, which matures from November and has ornamental red-tinged leaves. One of the traditional favourites is ‘Best of All’, which supplies firm, crispy hearts until the New Year.
The white varieties of cabbage are used in coleslaw and other salads and can be stored for around three months. Some varieties, such as ‘Tundra’ (pictured), have excellent winter hardiness and can be cut straight from the garden from November right until early spring in March; ‘Minicole’ is a compact variety that is ready from October, and will also keep well in the ground for some months.
What to sow in April
Cabbages are categorised according to their harvest time and the ones to sow now are the summer varieties and ornamental red cabbages which are delicious when shredded, sautéed and cooked in stock.
The keys to success are having a neutral-to-alkaline soil (if you haven’t got one, apply lime in autumn to reduce acidity) and firm ground to grow them in (so leave a good six weeks between digging and planting) as the cabbages won’t heart up in soft soil and will produce a shaggy head of leaves.
Sow them in a seedbed under cloches in rows 15cm apart and thin to 7cm when they emerge from the soil. Once the cabbages have 5-6 leaves transplant them to their growing positions by trowelling them from the ground.
To help the soil hold around the roots, water the rows well the day before lifting. Alternatively, if you suffer from slugs or your soil is cold and heavy, raise the plants in a greenhouse and prick out the seeds into 9cm pots.
Apply a general fertilizer such as blood, fish and bone or Growmore before planting and then set out the cabbages in staggered rows 30-45cm apart.
Cover the crop with horticultural fleece or enviro-mesh to keep off the cold and protect the young plants from pigeons and flea beetles that puncture holes in the leaves, seriously weakening plants.
Full of eastern promise
Chinese cabbage has been known in China and parts of Asia since the fifth century. Now a favourite ingredient in European cooking, it is easy to grow provided you wait until July to sow it. Any earlier and there is the risk that a sudden drop in temperature will cause the plants to bolt and produce flower heads. The same goes for a host of otherwise undemanding oriental vegetables: pak-choi, mustards and Japanese greens.
The mild flavour and crunchy texture of Chinese cabbages are good both in salads or a stir-fry. Look for ‘Kasumi' or ‘Early Jade Pagoda', both of which produce dense, mid-green heads. ‘Maruba Santoh' is a loose-leaved type with light green, round leaves that can be harvested five weeks after sowing.
Of the pak-choi cultivars, ‘Joi Choi', ‘Tatsoi' and ‘Canton Dwarf' are reliable varieties. When cooked, the glossy green leaves melt like spinach while the thick white stems remain crunchy like bean shoots. Mustards have a hot flavour so pick the leaves when small for salads or when mature for stir-fry. Look for ‘Red Giant', which has decorative green leaves mottled red. ‘Green in Snow' is hardy and will make a winter green if resown in late August.
Of the Japanese greens, ‘Mizuna' forms clumps of feathery dissected leaves and will be ready to eat three to four weeks after sowing. Use the leaves as for the mustards; the more you pick, the more they will produce.
Oriental greens make a good follow-on crop after broad beans or peas. While you wait for the final pickings, sow the seeds thinly in 8cm pots about two weeks before the space will be ready to plant up. Place them in partial shade, keep well-watered and watch out for slugs and snails. If you make your own biodegradable pots with a pot maker from the Organic Gardening Catalogue (all you need is newspaper), the seedlings can be planted in the ground in the pot to minimise root disturbance. The paper will disintegrate in the soil.
If you are sowing seeds directly into the ground, water it well then sow thinly into drills. Add a general fertiliser as a surface feed because the soil will be depleted from earlier crops. To maintain fast growth, the soil should be fertile and moisture-retentive.
Chinese cabbage and larger types of oriental greens need 30cm-38cm of space all round to produce heads. Tie the leaves with raffia as the Chinese cabbage begins to form a heart. Pak-choi can be thinned to 23cm apart; mustards and greens thinned to 10cm-15cm.
‘Mizuna', ‘Green in Snow' and ‘Tatsoi' can be sown in late August for a winter harvest that will go on until spring and can survive unprotected in a mild winter. Other oriental greens are frost-tender but if sown in September can be protected with a cloche or polytunnel to provide winter greens. These vegetables are prey to cabbage aphid, flea beetle and cabbage white butterflies. Pick off caterpillars and protect with a fine mesh or lightweight fleece.
Kitchen garden: Carrots
From the first root teased out of the summer's warm soil to the winter warhorse prised from frozen clods in the depths of December, the carrot (Daucus carota) is a permanent presence in our kitchen garden. It is easy to grow as long as you avoid manure (it causes the roots to fork), and is not fussy about soil types or nutrition. With some thinning and keeping a watchful eye for carrot-fly maggots, good crops of carrots can be raised in any garden.
Like many of its relations in the Umbellifera (now Apiaceae) family, such as celery, parsnips and parsley, carrots germinate poorly in cold wet soil. Wait until the soil temperature is at least 10C (50F). Place your palm on the surface and it should feel warm to the touch. The soil should also be moist just under the surface.
Carrots should be sown in drills, ie, straight lines, with at least 20cm (8in) between drills. The tilth for the drill should be as fine as possible so rake the soil back and forth until the crumbs are nearly the size of granulated sugar. Take out the drill by working a trowel back and forth until it is 1.5cm deep and then sprinkle the seeds along the drill so that they almost touch. Firm the soil back in and water well. When the seedlings have produced true leaves and are large enough to handle, maincrop carrots will need to be thinned to 5cm apart. Water the row back in after thinning. Summer bunching carrots such as ‘Amsterdam Forcing' or the Nantes types can be eaten as they are thinned. Keep the row watered in dry spells and harvest as you need them.
Whether it is smell or sight that attracts the fly, growing onions next to carrots is not an effective deterrent nor is the use of resistant varieties.
If allowed the fly will lay its eggs by the plant and the maggots will burrow into the root. The best way to stop this is to cover the crop with horticultural fleece. Lay the lightweight fleece loosely over the crop to allow the foliage to push the cover up as it grows. Secure the sides and ends with bricks or timber. For maincrop varieties, leave on right through the summer.
Organic maincrop carrots are cheap and freely available and I prefer the quicker growing, smaller and sweeter varieties such as ‘Amsterdam Forcing' and the Nantes types. Two other favourites of mine are the round baby carrots ‘Parmex' (Paris Market) and ‘Parabel'. If you prefer a large maincrop carrot for winter use, ‘Autumn King' is very reliable.
The early and quicker growing varieties of carrot are good candidates for pots. Fill a 30cm-deep pot with organic potting compost and scatter seed generously on the surface. Cover lightly and water. Thin by harvesting and always water the crop back in. There is no need for feeding but keep well watered and covered with fleece.
Early carrots are green on their crowns. What went wrong?
This condition is called green top and, because it affects the roots, is nearly always discovered after harvesting has taken place. It is due to the crowns of the carrot roots being exposed to direct sunlight while they were growing in the ground. Fortunately, there is little to worry about, as the affected carrots (unlike green potato tubers, which are poisonous) are still edible.
However, if they look a little unsightly, the tops should be removed before cooking. If you have more carrots growing outside, then try to protect them from this condition by lightly earthing up with soil to cover the tops of the developing roots.
Gardening: Beauty and a feast
Red arrows indicate crop rotation.
3. Sweet corn
4. Compost area
5. Seed beds
6. Runner beans
7. Cold frames & cloches
8. Potatoes (new & main crop)
9. Root vegetables
11. Peas and beans
12. Rhubarb, broccoli, kale, chicory & asparagus
4 Year Rotation Plan
Permanent crops such as herbs, rhubarb and artichokes do not need to be rotated and can be planted anywhere in the garden.
Intercropping: Make use of all the space available by growing rows of quick maturing crops between those which take longer to grow.
Example, sow radish with parsnips; lettuce between rows of peas; marrows between sprouts; spring onions with lettuce and radish between rows of cabbage.
Catch Cropping: Catch cropping means growing a quick maturing crop whenever space becomes vacant. Lettuce can be grown on the ridge of soil from a trench dug for celery. The lettuce will mature before the soil is needed for earthing up.
Successional Cropping: Successional cropping means providing a continuous supply of different vegetables over a long period as possible.
Digging is one of the first gardening basics that comes to mind. But why do it at all? Fair question. Some people think you shouldn't.
Firstly, soil needs to be well aerated; the spaces are as important as the soil itself. The channels made by earthworms help the process, while also carrying vital organic matter to a lower depth. But this takes a long time to achieve, and earthworms themselves thrive far better in soils that are not dense and stodgy. A plant's roots, you see, operate better in open soil - they get better anchorage and are able to explore further. Digging is also necessary to find out what your soil is like. It may look lovely and black on top but be full of clay a little way down. If this is the case, the roots will stay in the top layer and be more prone to drying out when it turns hot.
Now to depth. We talk about going one or two spits deep. A spit is the average length of a spade's blade or fork's teeth. Double digging goes two spits deep. It is laborious and often unnecessary. However, it does enable you to reach down to the subsoil and, if necessary, remove some, should it consist of solid clay. This can then be replaced with good stuff, such as top soil from elsewhere or bulky organic matter produced from rotted plant remains. The more of this that you can get into the ground, the better. Removing bad soil might be especially desirable if you were planting a tree or large shrub, but less so if we're talking about annuals and perennials, because their roots don't go so deep. For most operations, Fergus finds that, on our clayey soil, one-and-a-half spits deep is fine. This is a reasonable measure for all-purpose gardening, bar the biggest plants.
So, how to dig? If you are thinking of getting round the job with a mechanical digger, or Rotovator, then think again: Rotovators alone do not do a good job for this purpose. They can't go deep enough and they leave a pan, which is an impenetrable layer below the small depth to which they can reach. Use a spade or a digging fork and make sure that it feels comfortable for you. This is a very personal thing. Turn the soil over and break it up to get a tilth for planting. By tilth, we mean a relatively fine condition (but not so fine as to lose the soil structure). If you have turned it to a good depth, then a Rotovator may be helpful to obtain this texture which will, in turn, make planting or sowing easy.
If you dig in autumn or early winter, leave the clods you've turned rough and exposed to the weather, especially frost which breaks them down. Then Rotovate in spring. It is worth remembering that, whatever is to be planted, drainage must be good. This may involve structural work to your garden (such as installing special drains or channels) and you may want to seek professional advice. However well dug your garden is, plant roots get stifled if they sit in a bog.
Finally, remember, at the end, to leave a neat and tidy job. Sweep the path and make the soil look inviting to plant and not like a collection of bomb craters.
I realise, however, that I am preaching either to the converted or to the deaf.
Is the first week in December too late to plant garlic?
Garlic is usually planted in mid- to late autumn. It requires a sunny spot and a well-drained soil that is not too rich. However, in cold areas and gardens with heavy soil, garlic is best raised in modular trays during winter and planted outside in spring. Fill a tray with John Innes seed compost and plant a single clove 1in deep in the centre of each compartment — the pointed tip should face upwards. Place the container in a cold frame or sheltered position outside. In spring, plant the garlic about 6in apart and keep the site free of weeds. Once the leaves turn yellow and fade, uproot the bulbs and leave to dry — handle them carefully to avoid bruising. Store garlic by hanging them in bunches in a cool, airy and frost-free room.
Gooseberry bushes cropping well when first planted, and have recently put on huge growth of wood and leaves but produced few berries. They were pruned after cropping and mulched with garden compost.
There are two potential causes for non-fruiting gooseberries. Sometimes, when plants are overfed, they produce lots of growth at the expense of flowers or fruit. However, as they were given garden compost, pruning is likely to be the problem. Pruning the bushes after cropping is the wrong time and suggests that the method may be wrong. Gooseberries flower and fruit only on shoots that are at least a year old, so each year if the whole thing is cut back, it doesn't have a chance. Leave the plant to grow this summer.
In winter, when the leaves have dropped, select four or five of the strongest stems and completely remove everything else, including any weak or damaged wood. Each subsequent year, let four or five new canes develop, choosing them carefully to keep the centre of the bush as open as possible, so letting in plenty of air and sunlight. From the fourth year on, start removing the oldest stems. Continuing in this way, you will constantly replace the oldest wood while it is still fruiting and before it heads into decline.
Greenhouse mint which is yellow and distorted. This is caused by mint rust, and plants raised under cover are particularly susceptible, especially early in the season. The infected foliage turns pale and forms dirty orange spots on the undersides — the stems are often attacked, too. This is a nasty fungal disease and normally kills the plants, so it is best to throw them away and start again. However, you could try cutting the stems hard back to see if the new growth remains healthy. It is possible to prevent mint rust by taking cuttings every year, as older specimens are more susceptible. Fallen leaves and debris should be cleared away regularly, otherwise it will harbour the spores and cause re-infection.
Tom Petherick If you have room for only a few herbs, parsley (Petroselinum) should be one of them. By sowing it in spring and again in July, you can have a continuous supply of fresh sprigs from flat-leafed and curly varieties. Flat-leafed parsley tends to have a stronger flavour and is the choice of chefs. A third kind, Hamburg or turnip-rooted parsley, tastes like flat-leaved parsley. The roots are used to flavour the white sauce that is served with hot ham.
Leaf parsley in the garden Like most members of the Umbelliferae family, which also includes carrots, celery and parsnips, parsley is a slow germinator. Sow seed in pots of organic seed compost and keep a minimum glasshouse or windowsill temperature of 18C (65F). Germination can take a fortnight or longer. Prick the seedlings into individual 7cm (3in) pots filled with organic potting compost. Transplant into the garden when the roots have filled the pot. Fork a double handful of garden compost in and around the planting hole and plant 15cm apart in full sun. Keep well watered through the summer and feed once a fortnight with liquid seaweed. The plants raised from July sowings should be overwintered indoors, in pots.
In containers Raise as for the garden and transplant a single plant into a 9cm pot filled half with garden topsoil and half with organic compost. Alternatively, put three plants into a 30cm pot. Keep the compost damp and feed fortnightly.
Hamburg parsley Choose a site in full sun that has been manured the previous season and rake the soil to a fine tilth. Take out a drill an inch deep, then sprinkle the seeds in, a couple of millimetres apart. When large enough to handle, thin the seedlings out to 10cm apart and water the row back in. Leave to grow through the season, but do not feed. By late August the top, which is about 20cm square, will resemble a smaller flat-leaf parsley plant, while the buried root will be the size and colour of a small parsnip. The roots keep well in the ground over winter. Pot cultivation of rooting parsley is the same as for leaf parsley but the roots may not reach the size of an open-ground crop.
For the sauce Lift a root, cut off and keep the top, wash well, scrape or peel, and boil until tender. Push the root through a sieve and add to a béchamel sauce made with the boiled root juice. Chop some of the green top and add to the sauce.
For winter parsley, sow seeds in pots in late summer and bring them indoors in autumn.
Curly: moss curled.Flat-leafed: Italian giant, French plain. Organic seeds from Suffolk Herbs (01376 572456; www.suffolkherbs.com);
organic seeds and plants from Jekka's Herb Farm (01454 418878; www.jekkasherbfarm.com)
Growing parsnips and kohl rabi. I understand that they thrive better in alkaline soil — if so how much lime do I use per square metre? Also my soil is clay. How do I break it down? Last year I tried multipurpose compost.
To break up the texture of a clay soil you need fibre, of the kind found in old coarse garden compost — small stalks, etc. There is never enough, of course. A good alternative is spent mushroom compost, although this is alkaline and should not be used on already alkaline soils for fear of making the soil too alkaline. Manure which has been made with plenty of bedding straw is good, although made with large volumes of wood shavings it can rob the soil of nitrogen.
There is a new mulch of coarse, mineralised straw, called Strulch, which will break down into just the right material for relieving clay (www.strulch.co.uk; 01943 863610). An ordinary bale of straw, sprinkled with sulphate of ammonia (high nitrogen) and allowed to rot down is fine, too.
Coarse grit is also beneficial. Multi-purpose compost, as used for potting, has little value in breaking down clay; it is far too fine and expensive.
Both kohl rabi and parsnips are easy enough to grow, and their preference is not so much for an alkaline soil as a soil which is not acidic, so be sure of the lime content of your soil before you start adding lime. A cheap soil-test kit and a few tests will soon tell you what it is. Heavy clay soil of moderate acidity may require 800g per square metre, applied in autumn, to bring it up to the desired pH 6.5. Light soils require much less.
CHIT SEED POTATOES 1
CHIT SEED POTATOES 2 (jpeg)
START EARLY POTATOES (jpeg)
THE PERFECT SPUD FOR ALL SEASONS - ARTICLE
KITCHEN GARDEN (FEBRUARY)
GROW IN CONTAINERS - 2 articles
GROW WITHOUT SCAB
TOP-GROWTH KILLED BY FROST (jpeg)
HOW TO GROW (jpeg)
WITH SURFACE CRACKS
YEARLY PLANNER EARLIES(jpeg)
YEARLY PLANNER MAINCROP (jpeg)
Potato tubers covered in surface cracks. What can to do to protect the crop?This is caused by excessive water after a long, dry spell, leading to a rapid growth of the tubers and splits forming in the skins. The affected tubers can still be eaten, although they may be difficult to peel, and are susceptible to rotting, so use them as soon as possible. Keep your plants well watered, especially in warm, dry weather.
HOW TO GROW POTATOES IN A CONTAINER
You don’t need a garden to enjoy home-grown potatoes, just enough space on a sunny balcony or patio for a large pot. Rather than using potatoes from the greengrocer, you’ll get better results planting seed potatoes, which are certified disease free. When you get them home, place in a seed tray with the sprouts (eyes) facing upwards, and leave in a light, frost-free place. When the sprouts are 2cm (¾in) long they are ready to plant. This process is referred to as chitting. It is possible to harvest 2.3kg (5lb) of potatoes from just 4 seed potatoes.
Follow the steps for a bumper crop of potatoes
HOW TO GROW POTATOES IN A CONTAINER (2)
New potatoes are utterly delicious, and the eating experience is so much 4 richer for the small effort it takes to raise them. A few containers will yield enough to satisfy my rather greedy family with practically zero effort.
Find proper seed potatoes, in varieties such as 'Charlotte, 'Ratte' or 'Anya', at the garden centre — they will have lots of little shoots appearing. Lay them out with the largest shoot uppermost (an egg box is perfect for this), put them on your kitchen windowsill, or somewhere warm and light, for 6-8 weeks and watch as the shoots swell until they're about an inch long.
Then put four potatoes in a 12in pot, with 3in of multipurpose compost below and above them. If you water well, leaves should appear within a couple of weeks. Wait until they're 6in high, then add another 3in of compost so just the topmost inch of the plant peeps out.
Keep doing this, and watering regularly, until you can't fit any more compost in the pot, then sit back and wait for flowers — by which time each potato will have multiplied by at least five, and you can pull your harvest up to whoops of amazement.
First earlies are ready from June to July. They mature fast, in around 10 weeks, and have thin skins. Eat them straight after harvesting.
Second earlies ready from July to August, are bigger than first earlies and you can store them
Early maincrops are ready in August, and
Late maincrops from September. You can store both. They generally give bigger crops of larger potatoes with thicker skins.
Chitting (allowing shoots, or chits, to develop on the potatoes before planting) speeds early growth, but isn’t essential. Just put your seed potato end up in an egg box on a light windowsill.
Earthing up involves drawing up earth around the plant to cover emerging shoots (hence more tubers) and stops potatoes turning green.
How do I grow potatoes without scab? I have tried growing several varieties of first early potatoes but all have been covered in scab — and I do like potatoes in their skins. My soil is fairly neutral and I rotate the crops.
Scab is at its worst on hot, dry, limey soils, although the bacterium is present but not troublesome in most soil. Add no more lime, therefore, and work hard at getting more humus into the soil — compost, manure, whatever you can get — and use a generous mulch as well. Avoid varieties which are prone to scab too (eg, Desiree, Majestic, Maris Piper) and look to resistant ones (Admiral, Romano, Verity, Orla, Colleen, etc.)
The tubers of seed potatoes should always be induced to form small shoots (sprouts) before planting — this is vital for early and main-crop varieties. The best way to do this is by placing the tubers side by side in a tray (with the eyes facing upwards) and leaving in a cool, light and frost- free room for about six weeks. However, if they are exposed to warm temperatures, or the area is too dark, then the sprouts will be long and thread-like. The tubers can still be planted in this state but, for ease, some of the longest should be rubbed-off. It is essential to buy seed potatoes that are “certified” as disease-free because some viruses can have the same effect.
When storing seed-potato tubers after purchase they need to be cold (frost free) and dark, or they sprout too early and the brittle shoots can easily be broken. But when setting them to sprout prior to planting in early spring (“chitting”), they need to be somewhere light to encourage shoots.Direct sunlight, however, will cause the tubers to shrivel more than is beneficial. So a shed or garage window is good, or a shaded greenhouse. A cold frame is likely to be in full sun and a little on the cold side; a kitchen would be too hot. But chitting is not a precise art; all that matters is that they sprout.
Potatoes are easy to grow and, with careful selection of varieties, it is possible to harvest the tubers for most of the year. It doesn't even matter if you don't have room for a vegetable garden, as many are suitable for raising in containers.
When growing potatoes, it is essential to start with top-quality “seed” (small tubers) that have been certified as virus-free. These are usually “chitted” (induced to develop shoots) indoors before planting in containers or the ground — this is an important process for “extra-earlies” and “earlies” and useful with the later “maincrops”.
Stand the seed potatoes side by side in a tray, with the ends that have the most eyes facing upwards, and position in a cool, well-lit and frost-free room. The shoots will appear four to six weeks later and the tubers should then be planted.The first potatoes that can be harvested each year are extra-earlies — the best varieties are ‘Dunluce' and ‘Lady Christl'. Chitting of these varieties should begin this month. When they have sprouted, half-fill a 12in container (with drainage holes) using John Innes No 3 compost and plant three tubers inside — the shoots should face upwards and be 1in to 2in deep when covered. Position the pot in a frost-free conservatory or greenhouse and keep the soil moist. When the foliage is 3in high, surround with 2in of compost so only the tips are exposed. Repeat this process until the container is filled with earth. They will be ready for harvesting as succulent new potatoes 10 weeks after planting.
Alternatively, plant the chitted tubers outside in a sheltered spot and space them 12in apart — a well-drained soil in full sun is essential. To protect the shoots when they emerge above ground, cover with horticultural fleece (available from garden centres) if frost is forecast. Early potatoes come next and include varieties such as the dark-skinned ‘Red Duke of York'. First earlies are planted in mid-March to provide a crop in June or July. Second earlies are best planted in late March for harvesting in midsummer.
The key to success is to space the chitted tubers 12in apart, keeping them moist and protecting the shoots from frost — this can be done with fleece or by drawing a little earth over the top of them. Both are suitable for planting in outdoor containers — raise the bases slightly off the ground and use gritty mulches to deter slugs.
Maincrop potatoes are planted outside in April (with 15in between the tubers) and are ready for lifting from late August to early October. As well as popular types such as ‘Desiree', try ‘Pink Fir Apple', which has a knobbly skin but a delicious nutty flavour, or the blue-purple tubers of ‘Arran Victory'.Earlies and maincrops that are planted in the ground should be earthed-up when the haulm (leaves and stem) is about 9in tall — this encourages the production of underground tubers and helps drainage, preventing waterlogging. Break up the soil between the rows with a fork, remove all weeds and use a hoe to gently pile loose soil against both sides of the stems to create a 6in-high flat-topped ridge. During the rest of the growing period, the ground should be kept moist and weeds removed.
Occasionally, potatoes (especially maincrops) can succumb to blight. This fungal disease is most prevalent in a warm, damp season. The first signs are discoloured and brown patches on the foliage. Spores are then produced and washed by rain into the soil to infect and destroy the tubers. For this reason, it is important to avoid wetting the leaves when watering. Control is difficult but varieties such as ‘Cara' have a degree of resistance. If you have big problems with blight, it is best to grow extra-earlies and first earlies, as both are usually ready for lifting before the disease has time to damage the tubers.
Once the flowers open or the buds drop, earlies are ready to harvest. To be sure, scrape away a corner of the ridge and if the tubers are the size of a hen's egg, they are ideal. Remove the haulm of maincrops when the leaves turn brown and the stems wither. A week later, lift the tubers, remove any loose soil and let them dry for a few hours. Store in a wooden box in a dark, frost-free shed where they should last until spring.Marshalls, 01945 466 711; Thompson & Morgan, 01473 688 821, http://potatoes.thompson-morgan.com/uk/en
Now is the time to think about ordering your potato seed tubers to get a good crop of earlies in spring. If you haven't got space for a maincrop, make sure you grow some earlies as they have a special, earthy flavour. Growing your own allows for a wide choice of organic varieties that are not available to the supermarket shopper, and early potatoes are unlikely to be troubled by disease.
Give yourself enough time to chit (sprout) the seed tubers before planting — this will put the crop ahead by at least a fortnight. Each potato has a series of eyes (small indentations in the surface of the tuber from which shoots appear), mainly at one end. These eyes should be exposed to light and warmth to encourage the shoots to break. The moment my seed arrives I stand the tubers on end in a seed tray on a windowsill but out of direct sunlight. It takes three to four weeks for them to put out an inch of shoot: plant them at this stage, and they will land running.
Potatoes like fertile ground: at least a bucketful of well rotted manure or garden compost should be dug in for every square metre. Sprouted tubers should be planted 6in deep and 9-12in apart any time from the beginning of March in the South and a fortnight later in the North. Rows should be 3ft apart and in full sun. When the first clusters of leaves reach 4-6in high they should be earthed up. Walk between the rows and shovel or rake up the soil in front of you (to a depth of 4in or so) against the plant to form a ridge about 8in either side of the plant. Don't worry if you cover some of the leaves but be sure there are enough above the soil to protect the plant from frost and kill emerging weeds. Do the same again after a month. About 90 days after planting, lift a plant and investigate. If the potatoes are the right size for you, lift the crop and store in a paper or hessian sack.
A single tuber planted in a 12in pot filled half with well rotted manure and half with garden compost should produce 10 to 12 potatoes. Water only if the soil starts to dry out, and then do so thoroughly. A feed of liquid seaweed fortnightly through the third month of growth will help swell the tubers considerably.
‘Duke of York' is waxy to start with, floury with age. ‘Belle de Fontenay' is a salad potato that can be grown very successfully as an early. ‘Pentland Javelin' is a good cropper.
Early, summer radishes are much too thin. What went wrong?
A spindly crop of radishes is usually due to overcrowding, and this occurs when the seeds are sown too thickly in the ground. To prevent this and to ensure the seedlings can be left to grow in situ without the need for thinning out, space the seeds 1in apart in ½ in-deep drills. It is a good idea to soak the bottom of the drill and let the water drain away before sowing, as the moisture encourages rapid germination and healthy growth. If when the seedlings appear they are too close together, thin them so they are the correct distance apart. During the growing season, keep the area free from weeds and make sure the plants are regularly watered, especially in dry weather.
What's the best soil mixture to make a small, raised vegetable bed, about 30cm deep, and which vegetables will be most productive in this type of cultivation?
The best soil would be John Innes No 3. Add an annual application of good compost or manure in autumn, to raise the bed's fertility, as well as improve drainage and water-holding capacity. Think about crop rotation; not growing the same crop on the same soil year after year helps to prevent pests and diseases. Also, search out the mini-vegetables in seed catalogues.
What should I do with my autumn-fruiting raspberry plants after I have picked the fruits?
Autumn-fruiting raspberries, including ‘Autumn Bliss', are usually ready for harvesting in mid-September and, at the start of the month, the bushes may need to be covered with netting to protect the developing fruits from birds. Once the raspberries have been picked, the netting should be removed and the plants left alone until the following year. In mid-February, prune down all the canes to just above ground level. New ones will then grow through the spring and summer to provide fruits the following autumn. Spread a thick mulch of manure or well-rotted compost around the plants at the same time, as this will help to feed them through the growing season, conserve moisture around the roots and suppress weed growth.
By growing several varieties, you can pick rhubarb from March to November:
'Hawks Champagne' comes up early, has long scarlet stalks and tastes of wine.
'Victoria' is a mid season variety, cropping from late May until the first heavy frosts.
'Livingstone' crops from September to November, as long as you don't pull up too many sticks in spring.
I am keen to grow rhubarb in my vegetable patch for use next year. I have read that growing it from seed is difficult. Can you tell me if there is an online supplier of sets. I'd like to try more than one variety.
There is not much point growing rhubarb from seed. It is better to buy a named clone set of proven quality and performance. But if you plant this winter, you will not be picking next year. Even after planting in a really richly prepared hole, you ought to leave it untouched for a year, until established. Then you can start thieving and eating its stems.
The place to buy rhubarb sets is J. Tweedie Fruit Trees, Maryfield Road Nursery, Terregles, Dumfries DG2 9TH (01387 720880). John Tweedie does not have an online catalogue, but you can send a SAE for a printed one. He grows 30 varieties, and recommends ‘Canada Red' and ‘Strawberry Surprise' as among the best for colour and flavour, the latter being especially colourful when cooked.
There is something of the night about rhubarb that is grown in darkness to produce albino pink stems when winter is barely making way for spring. Rhubarb by day is a straightforward perennial plant that is easy to grow and manage. In the past, many gardeners relegated their clumps to neglected corners where nothing much else will grow, but I give it royal treatment. My rhubarb has a brick coldframe all to itself, the blacked-out top going on only at forcing time. I feed it and crop it modestly and am rewarded with healthy crowns that last 15 years or more.
Rhubarb grows quickly. The plant makes enormous roots and thick stems topped off by large leaves. To do all this it needs food.
Ideally, choose a site with full sun, but plants will tolerate some shade. At planting, which is any time after Christmas up until March, dig in at least two buckets of well-rotted horse manure per square metre, which is the space you should allow for each crown. Plants will arrive from the nursery either in tight bud or with young leaves breaking. Plant the crowns with the buds or leaves sitting just above the surface. Firm them in well and water. Do not harvest the stalks in the first year of growth.
In November the leaves will die off and disintegrate. Now apply a heavy mulch of manure or compost around the base of the plant but not over the crown. In the second season, at the beginning of February place a terracotta forcing pot, a dustbin or a deep bucket over the crown. Keep an eye out for slugs on the inside of the forcer. By the end of March you should be able to start harvesting: pull off the stalks at the crown as you need and replace the forcer. There is no need to water. I harvest three or four pickings of the forced crop, then leave the lid off and let the plant green up and the stems go dark red. In June stop picking to allow the plant to grow and nourish itself.
In containers, choose a pot at least 60cm (24in) in diameter and just as high — anything smaller will not give the plant enough nourishment to thrive. Fill it half with manure and half with an organic container compost and plant and treat as for the garden. Keep well watered in dry spells. Varieties ‘Hawke's Champagne' is my favourite for colour and flavour. ‘Timperley Early' and ‘Reed's Early Superb' are also good. ‘Brandy Carr Scarlet' suits northern gardens as it gets going earlier.
When and how should to plant rhubarb.
Rhubarb is best planted in October and November or from February to March. Choose a sunny spot with a moist, well-drained soil and dig over the ground thoroughly to remove all weeds. Before planting, incorporate plenty of organic matter into the earth and then space the sets 3ft apart with the buds just below the surface. Firm in well.In the summer, keep the plants moist during dry weather, apply the occasional liquid feed and remove any flowering shoots.
In the autumn, cut off the dead foliage, and then spread a mulch over the crowns in winter. The first sticks can be harvested the following spring and early summer; leave two or three leaves on each plant to avoid weakening them.
Best time to plant rhubarb
If you are lifting, dividing and replanting rhubarb from one bed to another, then late autumn is the best time for this, after the leaves have died down for the winter. Brand new rhubarb plants are more often bought in pots or received through the post in early spring, and they usually settle in well as long as they are planted promptly Whichever way you choose, make sure that your soil is well dug and conditioned with wellrotted organic matter, and keep watering new plants thoroughly during droughts for the first year after planting.
Plant out shallots – The February Garden
Most members of the onion family are easy to grow, including shallots, which I just can’t get enough of. You can fry them, sauté them, roast them, use them in salads, sauces and even pickle them. If you head too your garden centre or look in a seed catalogue you’ll find shallot bulbs to plant now. Try ‘French Jermor’ from Suttons, which is an Award of Garden Merit variety. This means the RHS thinks it’s one of the best around.
To grow them, first prepare the soil by digging it, then breaking it down to a crumbly finish with a rake. Using a dibber, make a hole and plant the shallot to half its height (see picture), keeping 20cm (8in) between bulbs. If you don’t have a vegetable area, try dotting a few among other plants in the border. Just keep shallots weed-free and by July each bulb will have produced eight more that are ready to lift and enjoy.
Best varieties to sow now (Feb)
‘French Jermor’, which has long bulbs with pink flesh; light-bulb shaped ‘Hative De Niort’; ‘French Delvad’ and ‘Golden Gourmet’, both producing rounded bulbs; ‘Topper’, which is good for pickling.
Plant on the shortest day and lift on the longest day. This is the old adage for the shallot and it is enough to get me out into the garden to work off gently the seasonal excesses once the soil is manageable. Nothing is more pleasing than to push a shallot bulb into the cool winter soil and watch it thrust its sturdy green claws skyward, untroubled by frost or biting winds.
Shallots are sweet, tender members of the onion family. They reach the size of a sweet chestnut — the leaves grow to about 12in (30cm) — and are foolproof to grow and delicious to eat, with a milder flavour than true onions. For some reason, organic shallots are difficult to find in the shops so growing your own organically is a double bonus.
From a single bulb planted any time after the shortest day (December 22 this year) up to the end of February, a crown of six to eight further bulbs will appear in a loose, open cluster on the soil surface as the spring turns to summer. They ripen through the summer until the foliage starts to brown. By mid-July it will have died off and you should then lift the bulbs.
IN THE GARDEN. Choose a site in full sun and rake the soil to a fine tilth (i.e., small crumbs no bigger than hazelnuts). Do not add any manure or even compost, as shallots do not like overly rich soil. Push the bulbs in up to their necks at eight inches apart with 12 inches between the rows. There is no need to water throughout their growing season. During the summer hoe off any surface weeds and ease the clump up with a fork once the foliage has shrivelled. Shake off any soil and dry them either spread out on the ground or in a shed; store them in a cool, airy shed, preferably hung up in a net, and they should keep for up to a year.
IN CONTAINERS. Shallots are shallow rooting, so any pot deeper than four inches is fine to use. They will grow happily alongside annual flowers in tubs that have been filled with garden or organic container compost but they will need watering if the compost starts to dry out.
Varieties ‘Golden Gourmet' produces pale yellow-skinned bulbs that store well and have a mild flavour, but I prefer the brown-skinned varieties such as ‘Pikant', which have more tang.
When should shallots be planted?
Shallots are easy to grow from “sets” (small bulbs), which are usually planted in February or early March. Choose fertile, well-drained soil in a sunny spot, lightly dig over the ground to remove all weeds and then rake the surface to a fine tilth. Create a shallow drill with a hoe, space the sets about 9in apart in the bottom and then surround with earth — the pointed tips should be just above ground level. Do not push the sets into the soil as this can damage them. In very sheltered gardens, you can plant shallots during January, but examine them regularly as birds have a tendency to pull them up. Replant any that have been lifted and place twigs over the top to prevent further disturbance.
How to grow turnips for winter
These fast-growing root vegetables are easy to raise from seed. The best varieties include ‘Manchester Market', for its hardiness, and ‘Golden Ball', which is compact and tender. In mid-July, select a light, well-drained soil that has not been manured recently. Dig and rake over the ground thoroughly. Create a drill of between half an inch and three-quarters of an inch with a hoe. Moisten the earth before sowing the seeds thinly and cover with soil. When the seedlings are about 1in high, thin them to 3in apart and then again to 6in apart once the leaves are almost touching. During the summer and early autumn, keep the area weed-free and water well in dry weather — otherwise you will get small, woody roots. In cold or wet gardens, the turnips should be lifted in early November. Twist off the leaves and store the roots in boxes of sand that have been placed in a cool shed. Alternatively, leave them in the ground and harvest as required.
1. Why have many of my greenhouse tomato fruits failed to develop in size?
When tomato fruits do not grow larger than a few millimetres in diameter, it is due to dry set. This condition is caused by the atmosphere inside the greenhouse being too hot and dry while pollination of the flowers took place. There is nothing that can be done to help the affected fruits, unfortunately. In future seasons, the best way to avoid dry set is to lightly spray the tomato plants every day with tepid water while they are in bloom, misting them either in the early morning or early evening. It is also a good idea to regularly damp down the floor of the greenhouse on hot days, as this will create a humid environment around the tomatoes.
2. After turning yellow, the leaves of an indoor cherry tomato plant curled and dried up from the bottom, others failed to grow. This could be due to a lack of magnesium. The yellow leaves become apparent at the bottom of the plant first before the leaves higher up are affected. There’s a simple remedy; give each plant a pinch of Epsom salts and water it in well.
The traditional way of storing onions is to string them together and hang them up. This is quite easy to do.
Ensure that the onions have been left to dry and ripen but still have pliable stems. Remove any loose outer skins and and trim off the roots. If necessary cut the stem to about 4 inches (10cm).
The length of the string is not really important but remember that the more onions that you place in the string the heavier it will be - and you will have to lift it, to hang it up. I have found that a length of string about 5ft (1.6m) long is about right though.
Fold the string in half and tie a knot at the loose ends to fasten them together.
To make working a bit easier I usually hang the string on the back of a door using a hook bent out of a piece of wire coat hanger but you can hang it on whatever is convenient to give a suitable working height.
Twist and form a loop in the bottom end of the string and place the neck of an onion in the loop. Tighten the loop around the neck. You will find that the onions own weight is sufficient to hold it in place. Cut off any excess stem to leave about 1 inch (2cm).
Add a second onion by weaving the stem around the string as in figure ?. Push the stem downwards and trim off any excess stem, leaving about 1 inch (2cm)
The third onion is woven in from the opposite side of the string in the same way. As you push each onion down it will lock the previous onion in place.
Continue adding onions from alternate sides until you reach the desired length. If you have too much string left at the end, simple knot it at the required length to form a smaller loop and cut off the excess.
Hang in a cool dry place to store.