Broom

Value to bees

Nectar

None

Pollen

Very high

As a honey crop

Not a honey source

Which bees, and why

Bumblebees are the main visitors, being heavy enough to trip the explosive keel reliably. The mechanism fires once per flower and cannot reset, so a tripped flower is finished — which means a bee has to keep finding untripped ones.

An explosive keel requiring a bee's weight to open. There is no nectar to reach, and the pollen is delivered rather than gathered.

Worth knowing

Zero nectar and very high pollen — one of the small group of plants including poppy, hazel and gorse that make the case for separate ratings unanswerable.

Flowering

In flower

April to June (northern hemisphere)

Four to six weeks in late spring, on acid and disturbed ground.

When nectar flows

None. Broom produces no nectar at all and offers only pollen, released explosively when a bee's weight trips the keel.

Year-to-year variation

Pollen is abundant and reliable. It will never be a honey source.

Growing it

Conditions

Full sun, poor acid free-draining soil. It fixes nitrogen and thrives on the worst ground.

Size

1-2.5 m.

Native range

Western and central Europe.

Suits

Large gardens, Hedgerow, Meadow or wildflower area

• Short-lived — often only eight to twelve years — and it will not regenerate from old wood, so prune lightly and young or not at all.
• Excellent on poor sandy banks where little else establishes.
• Do not plant it in North America, Australia, New Zealand or Chile, where it is a serious invasive.

What it looks like

An almost leafless shrub of stiff green ridged stems, covered in May with bright yellow pea flowers, followed by black pods that split audibly in hot weather.