QUESTION TIME

GOT A FRUIT OR VEG PROBLEM? ASK KG FOR HELP

THIS MONTH’S EXPERT PANEL:

GUY BARTER

RHS chief horticulturalist

EMMA RAWLINGS

Deputy editor, Kitchen Garden magazine

DAVID PATCH

Professional nurseryman, R V Roger Ltd

ANNE SWITHINBANK

Contributor to Radio 4’s Gardeners’ Question Time

STEVE OTT

Editor, Kitchen Garden magazine

OLD WIVES’ TALE OLD BEAN

I read somewhere that you should spray your runner beans with water when they flower to help them set. Is this necessary and if so, how does it help?

Tom Fawcett, Durham

ANNE SAYS: Spraying runner bean flowers with water is now widely considered to be an old wives’ tale and I agree. Should the weather be dry, you’d be better off directing the water at their roots and then spreading a good mulch of well-rotted compost over them to seal moisture in. Hot weather at night (above 16C/61F) can affect beans setting because high temperatures hinder pollen grains from germinating and producing a tube down to the ovary. I can remember my father watering his beans in the evening and spraying a little up under the foliage to cool them down. He always used to grow a white-flowered sort, like ‘White Lady’ in case we had a heatwave, as he believed they coped better with setting in hot weather. To sum up, I think spraying might actually damage the flowers but on hot nights watering in the evening would be an advantage. The new runner bean varieties with French bean don’t require cross-pollination and seem very ready to set in all situations. If you have trouble with setting, opt for ‘Moonlight’, ‘Firestorm or ‘Stardust’.