How to grow trilliums

Trilliums are extremely long lived. Although they can be slow to get going, they last for up to 25 years. By contrast, trillium flowers emerge in early spring and last for around three weeks. Trilliums are not considered invasive.

Bear in mind that trillium plant roots and berries are toxic to humans, cats and dogs, and will cause stomach upset. However their leaves can be eaten and are said to have a nutty flavour, though are more commonly used in medicine as a diuretic and antiseptic.

How to grow trilliums

Grow trilliums in moist but well-drained, neutral-to-acidic soil in partial shade to full shade. Water regularly to help the corms establish, especially during dry weather. Prune out dead, diseased or damaged foliage throughout the growing season and apply an annual mulch of leaf mould or homemade compost in spring.

Where to grow trilliums

Grow trilliums in partial to full shade, ideally in moist but well-drained, neutral-to-acidic soil. Planting between shrubs is said to protect trilliums from wind and other elements, which will keep them flowering for longer.

How to plant trilliums

Trilliums can be planted from dry bulbs (corms) in late summer. Plant them 7-10cm deep and water thoroughly so they establish before temperatures dip in autumn, then continue watering again during the growing season, especially during a dry spell. However, take care not to overwater the plants as trilliums suffer when the soil is waterlogged.

Alternatively, plant trilliums from young plants in spring – this tends to be a more successful method than planting from corms. Plant from mid-spring and keep plants well-watered until they become established, and again water when conditions become dry.

How to care for trilliums

Trilliums require little care. Prune out dead, diseased or damaged foliage during the growing season. In spring, it's a good idea to apply a mulch of leaf mould or homemade compost, as this will keep the soil moist and cool.

How to propagate trilliums

Established trillium clumps can be propagated by division after flowering. Simply dig up the plant as the foliage starts to die back and separate it into smaller clumps, ensuring each section has at least one bud and some roots. Grow the cuttings on in pots or the soil, covering the rhizomes with at least 5cm of soil or compost. If you're planting more than one cutting, space them 25cm apart.

You can also grow new trilliums from fresh seed saved from the spent flowers, however this is a long process as the seed goes through a process known as 'double dormancy'. This is where the seed requires a period of chilling (winter) for the root to develop but then another period of heat and cold for the shoot to grow. This means, if you sow ripe seed from your plants in pots of peat-free seed compost and place in a cold frame in shade, they will start to grow as plants in two years' time. Flowering may then occur a further two or three years later.

Problem solving

Trillium leaves are susceptible to the attentions of slugs and snails, while newly planted corms may attract squirrels.

Types of trillium to grow

Trillium grandiflorum

The most commonly grown trillium and the easiest to grow. Leaves are ribbed and shiny, and flowers are large, pure white and funnel-shaped. Height x Spread: 40cm x 30cm

• Buy Trillium grandiflorum from Crocus

Trillium erectum

Known as red trillium or purple trillium, this species bears nodding, three-petalled blooms in various shades of red to purple. Each trillium flower turns into a small red berry. H x S: 45cm x 45cm

• Buy Trillium erectum from Crocus

Trillium chloropetalum

Known as giant trillium or giant wake robin, it has marbled green leaves which are attractive in their own right, and large burgundy flowers. H x S: 50cm x 50cm

• Buy Trillium chloropetalum from Twelve Nuns Nursery