Wallflower Erysimum cheiri
Wallflower (Erysimum cheiri) is a biennial flowering plant in the Brassicaceae family, native to Southern Europe and the Aegean; naturalised on walls in western Europe. It grows 30–60 cm (12–24 in) tall and 30–40 cm (12–16 in) wide, wants full sun and low water, and is hardy to about -12 °C (10 °F). Space plants about 30 cm (12 in) apart.
Plan Wallflower in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
Wallflower at a glance
| Type | Biennial flowering plant |
|---|---|
| Family | Brassicaceae |
| Mature height | 30–60 cm (12–24 in) |
| Mature spread | 30–40 cm (12–16 in) |
| Spacing | 30 cm (12 in) centre to centre |
| Sun | Full sun, at least 6 h of direct sun a day |
| Water | Low; drought tolerance moderate, waterlogging tolerance none |
| Soil pH | 6.5–8 |
| Cold hardiness | About -12 °C (10 °F) once established (roughly USDA zone 8) |
| Heat stress | Likely above about 30 °C (86 °F) |
| Flowering | about 39–51 weeks after planting, for 6–10 weeks |
| Days to maturity | About 300 days from planting |
| Wind tolerance | Low |
| Pollinator value | High |
| Edible | Not grown as food |
| Native to | Southern Europe and the Aegean; naturalised on walls in western Europe |
| Common in gardens of | 🇬🇧 United Kingdom, 🇫🇷 France |
Is Wallflower toxic?
- People: moderately toxic
- Cats: moderately toxic
- Dogs: moderately toxic
- Parts: seeds, foliage
Contains cardiac glycosides (cheirotoxin); ingestion may cause nausea and heart-rhythm effects, and pet levels are inferred from the compound.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Wallflower
Good neighbours
- good With Rhubarb: Traditional lore says rhubarb planted near brassicas helps against clubroot and pests; the evidence is weak and not confirmed by trials. Evidence D
- good With Nasturtium: Nasturtiums act as a trap crop for cabbage white butterflies and blackfly, drawing some pressure away from brassicas. Evidence C
Shared pests and diseases
- Clubroot: Clubroot spores persist in soil up to 20 years; keep brassicas in a rotation. Evidence B
See Wallflower in a botanical garden
It grows in this sample garden, which you can walk through in 3D:
- Monet’s gardens at Giverny (70 plants)
Questions about Wallflower
- How far apart should I plant Wallflower?
- About 30 cm (12 in) apart, centre to centre. A mature plant spreads 30–40 cm (12–16 in).
- Does Wallflower need full sun?
- Full sun: at least 6 hours of direct sun a day.
- How much water does Wallflower need?
- Low water. Drought tolerance is moderate and waterlogging tolerance none.
- How cold-hardy is Wallflower?
- It tolerates about -12 °C (10 °F) once established, roughly USDA zone 8. As a biennial it is usually planted out after the last frost and flowers in its second year.
- When does Wallflower flower?
- About 39–51 weeks after planting, for 6–10 weeks.
- Is Wallflower poisonous to cats and dogs?
- For cats it is moderately toxic; for dogs moderately toxic; for people moderately toxic. Contains cardiac glycosides (cheirotoxin); ingestion may cause nausea and heart-rhythm effects, and pet levels are inferred from the compound.
- What grows well with Wallflower?
- Traditional lore says rhubarb planted near brassicas helps against clubroot and pests; the evidence is weak and not confirmed by trials. Nasturtiums act as a trap crop for cabbage white butterflies and blackfly, drawing some pressure away from brassicas.
Sources and evidence
Evidence grade C (C: plausible, mixed evidence).
- RHS Plant Finder, Royal Horticultural Society
- University extension gardening guides (general), Various land-grant university extensions
Notes and assumptions
- Typical garden-form values; cultivars and local conditions differ.
- Short-lived perennial grown as a biennial: sow in early summer, plant out in autumn, flowers March to May. Susceptible to clubroot, so avoid brassica beds.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Broccoli Brassica oleracea var. italica
- Cauliflower Brassica oleracea var. botrytis
- Cabbage Brassica oleracea var. capitata
- Kale Brassica oleracea var. sabellica
- Radish Raphanus sativus
- Bok choy Brassica rapa subsp. chinensis
- Brussels sprout Brassica oleracea var. gemmifera
- Kohlrabi Brassica oleracea var. gongylodes