It’s always a sign of a good garden plant if it has lots of common names, and this plant has. It grows in Europe and North America, with different species having evolved on either side of the Atlantic. The European species, Erythronium dens-canis, appears right across Central and Southern Europe to Asia and Japan. It is commonly known as dog’s tooth violet. It has flowers that vary from white to lilac pink and purple-pink, but not really violet.

The dog’s tooth part refers to the pointed tooth-like white bulbs. It is a lovely little flower for spring flowering in March and April, each flower carried singly on its nodding stem.

The plant’s natural habitat is open woodland and mountain meadows. It is a member of the lily family and its leaves and bulbs were traditionally consumed as food. The leaves are broad and held low, just a couple of leaves to each bulb, and they are speckled with brown and purple. The dog’s tooth violet has flowered well this spring, very pretty in light grass cover.

The American erythroniums are much bigger plants and there are several species. The one most like the European species is Erythronium revolutum, with lilac-pink flowers that may be carried on the stem. It is about twice the height of the dog’s tooth violet, reaching 30cm tall. It looks like a bigger version, but it is more elegant.

This species is known as the trout lily because it is heavily mottled with brown markings. Erythronium californicum is about the same height, with pale creamy-yellow flowers with orange markings and the leaves are lightly mottled. The leaves of these species are much longer and wider than the dog’s tooth violet.

Erythronium grandflorum is smaller in size, but has relatively large, yellow flowers, 5cm across and the leaves are not marked. This one is known as a glacial lily because it appears in high mountains, its bulbs a staple food of bears.

Another yellow-flowered species is Erythronium tuolumnense, which is native to central California. Its leaves are plain green, not mottled. It is a parent, along with White Beauty, of the best-known American trout lily, namely Pagoda. This is a very robust and vigorous variety, with beautiful yellow flowers, reflexed in Turk’s cap fashion, as are most of the erythroniums, and having broad brown-mottled leaves.

Of the many kinds, only the European dog’s tooth violets White Beauty and Pagoda are much grown in gardens. These are easily the best forms and are excellent garden flowers for March to May, the yellow American kinds flowering a bit later.

Even though the reflexed flowers appear remarkably delicate, these are much tougher plants than expected. They are truly perennial, lasting for decades and bulking up each year. They are happy under light shade of trees, growing out their leaves and flowering before leaves appear on trees. They cope well with tree root competition and summer drought, the leaves withering away by mid-summer.

They do not like the shade to be too heavy as this can reduce or stop flowering, and the plants may fade out eventually. A few hours’ sunshine is all they need. After flowering, to increase numbers, established plants can be lifted and the clump of bulbs separated with stems and leaves attaching to each group, and re-planted immediately.

Give a mulch of leaf mould in winter or early spring to retain moisture and improve growth. Watch for slugs and snails in spring as they can damage the flower stems as they emerge and afterwards. CL

Moving bulbs

Daffodils and other spring bulbs, snowdrops, crocuses and scillas, have finished flowering and can be moved now. Perhaps they need to be moved for some reason, such as crowding out and failure to flower, or that just they are needed somewhere else.

Be careful when lifting a clump of bulbs. Sometimes they can be quite deep. Pull the bulb clump apart into clusters of a few bulbs and lay these out randomly in a natural slew of flowers. Using a spade, lift a half-spade of soil, drop the clump in and replace the soil.

Firm the bulbs and water if possible to settle them. Don’t worry about depth as bulbs find their own depth and don’t worry about bulb foliage lying on the ground – it will still grow well.

This week

Trees, shrubs & roses

Although the main planting season is over, all kinds of pot-grown trees and shrubs can still be planted. Watering is important in making sure these plants properly take root. Rose bushes are making very vigorous growth and should be sprayed to control blackspot disease in wet weather.

Flowers

Watch for slug and snail damage during these weeks. Many plants are attacked as they come through the soil and sometimes this is difficult to spot. Bedding plants should be regularly watered and given liquid feed to get good size. Begonias and dahlias can be potted up and gladiolus can be planted.

Fruit, vegetables & herbs

Control weed seedlings by hoeing between the rows and hand-weeding in the rows. Thin vegetables that need it as they reach a suitable size. Thinning is best done early, but beware of snail damage after thinning. Vegetable seed sowing can continue, especially of main-crop vegetables.

Lawns

Lawns that are pale, with slow growth, should be fed now with lawn fertilizer or high-nitrogen fertilizer, but just enough to green the grass, not so much as to cause vigorous growth and extra work mowing. At most, 30g per square metre should be applied when rain is due.

Greenhouse & house plants

Overgrown house plants can be cut back now and well watered and fed until they show signs of new growth. Houseplants can be re-potted now if they are pot-bound and inclined to topple over. All greenhouse plants should be fed now and watered well to get the best benefit of the season.