Wallflower

Sun

Full sun; tolerates light shade but flowers less freely.

Water

Water regularly while establishing, then during prolonged dry spells. Avoid persistently wet soil, especially in winter.

Soil

Well-drained, moderately fertile soil, preferably neutral to alkaline. Tolerates chalky, stony and relatively poor soils.

Height

1-2.5 ft (0.3-0.75 m)

Spread

1-2 ft (0.3-0.6 m)

Flowers

Spring to early summer; fragrant clusters of yellow, orange, rust, red, cream or purple flowers, depending on the selection.

Foliage

Evergreen. Narrow, lance-shaped green to grey-green leaves on branching stems that become woody at the base.

Growth

Moderate to fast; summer-sown plants usually flower the following spring.

Care needed

Medium

• Pollinators
• Drought tolerant
• Low allergen
• Fragrant

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.3 ft (0.39 m)

3. After 2 years

   1.6 ft (0.49 m)

4. After 3 years

   1.7 ft (0.53 m)

   full size

About 2 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Toxic

Growth rate

Fast

• Plant in a sunny position with free drainage; use raised beds or containers where winter soil stays wet.
• Water new plants until established, then let the soil surface dry between waterings.
• Avoid rich manure and heavy nitrogen feeding, which encourage soft growth rather than flowers.
• Space plants 1-1.5 ft (0.3-0.45 m) apart to allow airflow.
• Keep mulch away from the crown and woody stem bases.

Pruning. Remove fading flower stems to prolong the display unless you want seed. If keeping plants after flowering, lightly shorten leafy shoots, but do not cut deeply into bare old wood.

Spring

Check moisture during dry weather and enjoy the main flowering display.

Late spring

Remove faded flower stems, or leave a few pods to ripen for seed.

Early summer

Sow seed thinly in pots or a nursery bed for flowers the following spring.

Summer

Thin or pot on seedlings; pinch young growing tips once to encourage branching.

Autumn

Plant sturdy young plants in their final positions while soil is still workable.

Winter

Check that water drains freely and remove fallen leaves lodged around plant bases.

• Plant in groups among tulips and daffodils for scented spring bedding.
• Use along sunny paths or beside entrances where the fragrance is easy to notice.
• Combine warm-coloured selections with blue forget-me-nots for strong spring contrast.
• Grow in sunny gravel beds or at the foot of old walls where drainage is good.

Garden styles it suits: Cottage garden, English country, Traditional, Dry gravel garden, Sensory garden and Pollinator garden.

Plant it with: Tulips, Daffodils, Forget-me-nots, Pansies, Grape hyacinths and Sweet alyssum.

Wildlife: The flowers provide nectar and pollen for bees and other spring insects. Single-flowered forms offer easier access than densely double forms.

• Clubroot causes swollen roots, poor growth and wilting: remove affected plants and avoid planting wallflowers or other cabbage-family plants in contaminated soil.
• Root and crown rot develop in wet soil: improve drainage, keep crowns clear and replace badly affected plants.
• Flea beetles make small holes in young leaves: protect seedlings with fine insect mesh and keep them growing steadily.
• Aphids cluster on soft shoots: wash them off with water or use insecticidal soap according to the label.

Wallflower contains cardiac glycosides and should be treated as poisonous to people, cats, dogs and horses. All parts, including seeds, should be kept out of reach; ingestion can cause digestive upset and potentially serious heart effects. Contact a poison service or veterinarian promptly if it is eaten.

• Stock (Matthiola incana)

  Stock usually has broader, softer, densely grey-hairy leaves and thicker flower spikes, often with double flowers. Wallflower has narrower leaves and typically four-petalled flowers on branching stems.

• Flax-leaved wallflower (Erysimum linifolium)

  It generally has narrower, greyer leaves and lilac-purple flowers over a longer season. Garden wallflower hybrids can be difficult to distinguish reliably without a plant label.

The common name refers to its habit of growing in cracks in old walls, while cheiri comes from an Arabic name for a fragrant flower.

Propagation. Sow seed in late spring or early summer for flowering the following spring; seedlings may differ from the parent. Take non-flowering softwood cuttings in late spring or early summer to preserve a particular selection.

Accepted botanical name

Erysimum cheiri

In the US and Canada

Introduced in Canada and the lower 48 states.

Sources: GBIF (CC BY 4.0) and USDA PLANTS. The care and design notes are LandscapeGPT's own.