Garden flowers

Wallflower

ErysimumBrassicaceae
Also: Erysimum, Perennial wallflower
AT A GLANCE
Full sun Water: little H4down to −10 °C 45–75 cm tall · 45–60 cm wide In a pot: yes
Flowering · UK
Flowering · Northern Italy
Flowering · Central Italy
Flowering · Southern Italy and islands

Plant into free-draining ground in spring and start trimming lightly from the first year; a wallflower that is never trimmed becomes woody far sooner.

Care

Light

Full sun — needed for compact growth and continuous flowering.

Water

Low — drought-tolerant, and far more often killed by wet than by dry.

Soil

Poor, free-draining, preferably alkaline soil — it grows naturally on walls and chalk. Rich or wet ground shortens its already short life.

Pruning

Deadhead the spent spikes continuously to keep it flowering, and trim the whole plant lightly after the main flush. Never cut back into old bare wood — it will not reshoot from it.

Feeding

Don't feed. Wallflowers flower themselves to exhaustion on poor soil, and feeding produces leafy growth, fewer flowers and a plant that splits open in the middle.

Propagation

Take semi-ripe cuttings in late summer as a matter of routine: perennial wallflowers are short-lived, often only three years, and cuttings are how you keep a favourite going. The biennial bedding kinds are raised from seed sown in early summer for the following spring.

Month by month

Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.

  1. AprilDeadhead the first spikes as they fade to keep the display going. how ›
  2. JulyTrim lightly all over after the main flush — never into old wood. how ›
  3. AugustTake cuttings as insurance; these plants are short-lived by nature. how ›

Months based on climate: UK. Your choice stays on this device.

  1. AprilDeadhead the first spikes as they fade to keep the display going. how ›
  2. JulyTrim lightly all over after the main flush — never into old wood. how ›
  3. AugustTake cuttings as insurance; these plants are short-lived by nature. how ›

Months based on climate: Northern Italy. Your choice stays on this device.

  1. MarchDeadhead the first spikes as they fade to keep the display going. how ›
  2. JulyTrim lightly all over after the main flush — never into old wood. how ›
  3. AugustTake cuttings as insurance; these plants are short-lived by nature. how ›

Months based on climate: Central Italy. Your choice stays on this device.

  1. MarchDeadhead the first spikes as they fade to keep the display going. how ›
  2. JulyTrim lightly all over after the main flush — never into old wood. how ›
  3. AugustTake cuttings as insurance; these plants are short-lived by nature. how ›

Months based on climate: Southern Italy and islands. Your choice stays on this device.

Common problems

Short life

How to spot it. A plant that was excellent for two or three years suddenly goes woody and dies.

What to do. Normal for the genus — keep replacing it from cuttings.

Splitting open

How to spot it. The plant splays apart from a bare woody centre.

What to do. Trim lightly and regularly from the start; an old split plant is best replaced.

Club root and brassica pests

How to spot it. Stunted growth, distorted roots — it is a brassica.

What to do. Do not plant where brassicas have grown recently.

Popular varieties

Erysimum ‘Apricot Twist’45–60 cm × 45–60 cm · April–AugustApril–AugustMarch–AugustMarch–August
Erysimum ‘Bowles's Mauve’AGM60–75 cm × 60–75 cm · March–SeptemberMarch–SeptemberFebruary–SeptemberFebruary–September
Erysimum ‘Winter Orchid’40–50 cm × 40–50 cm · February–MayFebruary–MayJanuary–AprilJanuary–April

Questions

Wallflower: is it hardy?

H4: Hardy through an average UK winter. It survives down to −10 °C.

Can it grow in a pot?

Yes — a pot suits it, since the drainage is sharper than most border soil.

Wallflower: when do you prune it?

Deadhead the spent spikes continuously to keep it flowering, and trim the whole plant lightly after the main flush. In the calendar for UK, pruning falls in July.

Wallflower: when does it flower?

In the climate of UK it flowers in March–August.

When do you feed it?

Don't feed. Wallflowers flower themselves to exhaustion on poor soil, and feeding produces leafy growth, fewer flowers and a plant that splits open in the middle.