Field bean

Value to bees

Nectar

High

Pollen

High

As a honey crop

Minor honey crop — a surplus only locally or occasionally

Which bees, and why

Long-tongued bumblebees enter the flower properly and pollinate it. Short-tongued species, particularly buff-tailed bumblebees, bite a hole at the base and rob the nectar without pollinating — and honey bees then use the holes the bumblebees made. Bean fields are one of the best places to watch nectar robbing in action.

The corolla is deep enough to require a long tongue, which is why short-tongued species rob it rather than entering.

Worth knowing

Good on both counts, and unusual in offering nectar from two different structures.

Flowering

In flower

May to July (northern hemisphere)

Spring-sown crops flower in June and July; autumn-sown crops flower earlier, from May.

When nectar flows

Substantial where acreage is large, from both the flowers and the extrafloral nectaries on the leaves.

Year-to-year variation

A reliable crop where beans are grown at scale. Bean honey is not usually separated commercially but contributes substantially to mixed summer honey in arable regions.

Growing it

Conditions

Full sun on heavy moisture-retentive soil, and hardy enough to be autumn-sown in mild regions.

Size

60-150 cm tall depending on variety.

Native range

Probably the Near East, and cultivated across Europe, North Africa and Asia since prehistory.

Suits

Small gardens, Large gardens, Farm scale

• Autumn-sown crops flower earlier and are less affected by blackfly.
• Pinch out the growing tips once pods have set, which reduces blackfly and directs energy into the pods.
• It fixes nitrogen; follow it with a hungry crop rather than fertilising.

What it looks like

An upright annual with square hollow stems and grey-green paired leaflets, carrying clusters of white flowers each marked with a bold black blotch on the wings. Dark nectaries show as small black spots on the leaf stipules.