Wallflower

Value to bees

Nectar

High

Pollen

Moderate

As a honey crop

Feeds the colony but rarely yields a surplus

Which bees, and why

Worked by honey bees, bumblebees, solitary bees and butterflies across three seasons. Its value is duration rather than intensity — it is rarely the busiest plant in a garden and it is very often the only one flowering in early March or late October.

Short four-petalled flowers with nectar within reach of short-tongued bees.

Worth knowing

Good nectar across an exceptionally long season, from a small drought-proof plant. Very few things offer eight months of forage from one position.

Flowering

In flower

March to November (northern hemisphere)

Genuinely this long for the sterile perennial hybrids, which flower almost continuously because they cannot set seed and stop.

When nectar flows

Steady and accessible, in short four-petalled flowers with the nectar within easy reach.

Year-to-year variation

Extremely dependable and drought-tolerant. Not a crop.

Growing it

Conditions

Full sun, poor sharply drained soil, and preferably a wall or a gravel bed. Rich damp ground shortens its life considerably.

Size

45-80 cm.

Native range

Southern Europe; the perennial garden forms are hybrids of Mediterranean species.

Suits

Containers and window boxes, Small gardens, Large gardens, Walls and fences

• Short-lived — three to four years — so take cuttings each summer to keep a succession going. They root very easily.
• Trim lightly after the main flush; do not cut into old wood, which will not regenerate.
• 'Bowles's Mauve' is sterile and therefore flowers far longer than the seed-setting biennial wallflowers, which is a rare case where a garden hybrid outperforms the species for bees.

What it looks like

A woody-based evergreen subshrub with narrow grey-green leaves and dense spikes of four-petalled scented flowers in mauve, orange, yellow or red.