From the family Liliaceae
These plants are widely distributed throughout the world. The onion goes back to a time before historians, and has been in cultivation so long that its country of origins are now uncertain although most agree that it originated in Central Asia. It was probably introduced to Europe by the Romans. The name seems to have been derived from the Latin word 'unio' meaning a large pearl. In the middle Ages it was believed that a bunch of onions hung outside the door would absorb the infection of the plague, saving the inhabitants. From this came the scientific recognition that its sulphur content acts as a strong disinfectant. The juice of the onion was used to heal gunshot wounds and burns caused by gunpowder.
Species
There are many, many varieties of Onion; the following information concerns the two that have herbal qualities.
Allium fistulosum
Welsh Onion
Also known as Japanese Leek. Evergreen hardy perennial. Ht60cm-90cm (2-3ft). Flowers of second year's growth greenish yellow in early summer. Leaves, green hollow cylinders. This onion is a native of Siberia and extensively grown in China and Japan. The name Welsh comes from 'walsch' meaning foreign.
Allium cepa Proliferum Group
Tree Onion
Also known as Egyptian Onion, Lazy Man's Onions. Hardy perennial. Ht 90- 150cm (3-5ft). Flowers small greenish white appear in early summer in the same place as its bulbs. It grows bulbs underground and then, at the end of flowering, bulbs in the air. Seeing is believing. It originates from Canada. It is very easy to propagate
Cultivation
Propagation
Seed
Welsh onion seed loses its viability within 2 years, so sow fresh in late winter, early spring under protection with a bottom heat of between 15°C (60°F) and21°C (70°F). Cover with Perlite. When the seedlings are large enough, and after a period of hardening off, plant out into a prepared site in the garden at a distance of 25cm (9in) apart. The tree onion is not grown from seed.
Division
Each year the Welsh onion will multiply in clumps, so it is a good idea to divide them every 3 years in the spring. Because the tree onion is such a big grower, it is a good idea to split the underground bulbs every 3 years in spring.
Bulbs
The air growing bulbils of the tree onion have small root systems, each one capable of reproducing another plant. Plant where required in an enriched soil either in the autumn, as the parent plant dies back, or in the spring.
Pests and Diseases
The onion fly is the curse of the onion family especially in late spring, early summer. The way to try and prevent this is to take care not to damage the roots or leaves when thinning the seedlings and also not to leave the thinning lying around, the scent attracts the fly.
Another problem is downy mildew caused by cool wet autumns; the leaves become velvety and die back. Again, too warm a summer may encourage white rot. Burn the affected plants and do not plant in the same position again.
Other characteristic diseases are neck rot and bulb rot, both caused by a Botrytis fungus that usually occurs as a result of the bulbs being damaged either by digging or hoeing.
Onions are prone to many more diseases but, if you keep the soil fertile and do not make life easy for the onion fly, you will still have a good crop.
Maintenance
Spring: Sow the seed; divide 3-year-old clumps of Welsh and tree onions. Plant bulbs of tree onions.
Summer: Stake mature tree onions to stop them falling over and depositing the ripe bulbils on the soil.
Autumn: Mulch around tree onion plants with well-rotted manure. Use a small amount around the Welsh onions.
Winter: Neither variety needs protection.
Garden Cultivation
Welsh Omens
These highly adaptable hardy onions will grow in any well-drained fertile soil. Seeds can be sown in spring after the frosts, direct into the ground. Thin to a distance of 25cm (9in) apart. Keep well watered throughout the growing season. In the autumn give the area a mulch of well-rotted manure.
Tree Onions
Dig in some well-rotted manure before planting. Plant the bulbs in their clusters in a sunny well-drained position at a distance of 30-45cm (12-18in) apart. In the first year nothing much will happen (unless you are one of the lucky ones). If the summer is very dry, water well. In the following year, if you give the plant a good mulch of well-rotted manure in autumn, it grows to 90-150cm (3-5ft) and produce masses of small onions.
Harvest
Welsh onions may be picked at any time from early summer onwards. The leaves do not dry well but can be frozen like those of their cousin, chives. Use scissors and snip them into a plastic bag. They form neat rings; freeze them.
The little tree onions can be picked off the stems and stored; lay them out on a rack in a cool place with good ventilation.
Culinary
Welsh onions make a great substitute for spring onions, as they are hardier and earlier. Pull and use in salads or stir fry dishes, chop and use instead of chives.
Tree onions provide fresh onion flavor throughout the year. The bulbils can be pickled or chopped raw in salads (fairly strong), or cooked whole in stews and casseroles.
Pissaladiere
Serves 4-6
4 tablespoons olive oil (not extra virgin)
20 tree onions, finely chopped
1 clove garlic, crushed
1 dessertspoon fresh thyme, chopped
Salt
Freshly ground black pepper 360g (¾ lb) once-risen bread dough
250g (½ lb) ripe tomatoes, peeled and sliced
60g (2oz) canned anchovy fillets, drained and halved lengthways
16 large black olives, halved and pitted
Heat the olive oil in a heavy frying pan, add the onions, cover the pan tightly and fry, gently stirring occasionally for 15 minutes. Add the garlic and the thyme and cook uncovered for 15 minutes, or until the onions are reduced to a clear puree. Season to taste and leave to cool. Pre-heat the oven to 200°C (400°F, Gas mark 6).
Roll the bread dough directly on the baking sheet into a circle 25cm (10in) diameter. Spread the pureed onions evenly over the dough, put the tomato slices on the onions and top with a decorative pattern of anchovy fillets and olives.
Bake for 5 minutes. Reduce the oven temperature to 190°C (375°F, Gas mark 5) and continue to bake for 30 minutes or until the bread base is well risen and lightly browned underneath. Serve hot with a green herb salad.
Other uses
The onion is believed to help ward off colds in winter and also to induce sleep and cure indigestion. The fresh juice is antibiotic, diuretic, expectorant, antispasmodic, so useful in the treatment of coughs, colds, bronchitis, laryngitis and gastroenteritis. It is also said to lower the blood pressure and to help restore sexual potency which has been impaired by illness or mental stress.
Container growing
Welsh onions can be grown in a large pot using a soil-based compost, and make sure it does not dry out. Feed regularly throughout the summer with a liquid fertilizer. Tree onions grow too tall for containers.
