Beans: Start your runners indoors

Martyn Davey, Head of Horticulture and Design, Easton College
Monday, July 9, 2012
10:33 AM

Question: The runner beans I have been putting in the ground have just not germinated. Should I start again with a fresh pack of seeds and/or germinate them indoors first? (J Davey, via email)

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Runner beans will always grow best when sown indoors as this will allow for an earlier crop. Sow the beans in 10cm pots at the end of April in a heated greenhouse. I like to use a peat-based multipurpose compost as this gives proven good results, although you can use peat-free or peat-reduced compost – in which case I would favour a coir-based one rather than some of the woodchip mixes. You may also want to reuse the inside of toilet rolls as pots as these can be planted direct into the soil and minimise root disturbance. When a reasonable size they can be planted out, usually at the end of May, 23cm apart.

The traditional method of growing is to sow a double row with the two rows 45cm apart; this makes supporting the plants easier; I use 2.6m long canes and make a wigwam for them to grow up. When sowing direct into the garden sow the seeds of runner beans from late May to the end of June 5cm deep and 23cm apart. They need to be kept moist, and protect from rats and mice particularly – but squirrels will also dig them up. Slugs and snails feed on the young seedlings (and this has been a bumper year for them). You’ll see the tell-tale slime trail of slugs and snails on the soil around your crop, as well as on the leaves.

There are many ways to control slugs and snails, including beer traps, sawdust or eggshell barriers and copper tape. Experiment, as you may find some more successful than others. Traditional slug pellets contain metaldehyde, which can harm other wildlife, pets and young children if eaten in quantity. Slug pellets or powders based on aluminium sulphate or ferric phosphate are less toxic.