We all know that beans are a musical fruit, or good for your heart, depending on which version of the rhyme you learned when you were a nipper, but in the UK at least no vegetable garden or allotment plot is complete without a wigwam foaming with scarlet-flowered runner beans.
The reason? Well, not only do they make a delectable vegetable, they are drop-dead gorgeous too.
Sowing and Growing Runner Beans
Runner beans were traditionally planted atop filled-in trenches dug the previous autumn and stocked with well-rotted manure or shredded newspaper. Kitchen waste will work too, because the main reason for doing this is to provide a deep, moist root run that will help runner beans to resist drought. Drought is a major enemy of beans, so avoid this at all costs.
Start sowing runner beans in spring and keep sowing every couple of weeks until early summer to spread out the harvest. Exactly when to sow will depend on your climate, so check out our Garden Planner for customised advice. The earliest seeds can be sown in modules or seed trays in a greenhouse, tunnel or on a sunny windowsill for transplanting later on.
Runner beans dislike cold soil, so wait until the soil has warmed to at least 10ºC (50ºF) before planting them out. You can warm soil a week or so in advance of sowing or planting using cold frames, cloches, horticultural fleece, or even just sheets of plastic.
Later sowings can be made directly where they are to grow, but beware of hungry slugs and make sure to protect seedlings from wind damage. Covering them with a cloche (even a recycled plastic bottle will do) will provide all the shelter they need until they establish.
In cool or windy locations you can protect plants and boost pod production by growing them to maturity in a greenhouse or tunnel – just make sure to ‘stop’ the plants, or pinch out the growing tips, when they near the roof.
While closely-related French beans are self-pollinating, runners need help from pollinators such as bees, so yields will be hampered by a wet, cold summer when insects are unlikely to be flying. A dry summer is bad news too, so make sure to water during rainless spells and mulch to preserve that moisture.
Beans are usually pretty trouble-free, but keep an eye out for black bean aphids infesting the growing tips. If this happens, clip off the tips and dispose of them.
Supporting Runner Beans
Get supports in place before planting your runners. Any frames or trellis need to be sturdy enough to support these lanky beans, which grow to well in excess of 2m (6.5 feet) tall and which will become extremely heavy when laden with pods. Netting is often used along with canes or poles to allow the vines to clamber about freely.
Bean wigwams look just as attractive in the flower garden as they do in the vegetable garden. Runner beans were originally grown purely as ornamental plants, so you can find exciting flower colour choices such as ‘Scarlet Runner’ or the ravishing red-lipped white flowers of ‘Painted Lady’.
You may need to tie young plants in to their supports initially, but once they’ve got a grip they should manage on their own. If they’re catching the wind they may need to be tied in at intervals.
When the plants reach the top of their supports, pinch out their growing tips to help divert energy into flower and pod production – and to avoid the plants turning into a jungle of tangled stems and foliage.
Such tall, leafy plants will cast shade, so plan your garden to include shade-loving crops behind your towering beanstalks.
Harvesting Runner Beans
Keeping up with weeding, watering and mulching is important while the beans are growing. Apply an occasional liquid feed too. Harvesting will commence around midsummer and continue until the first frosts. Runner beans will crop slightly later than French beans, so for variety and to extend the season it can be worth growing both.
Pick your beans while they’re still quite small to avoid any stringiness, though having said that modern cultivars are usually bred to be stringless. Pick at least every other day, because you’ll be astounded at how rapidly a bean pod can grow – they seem to go from flat to fat in the blink of an eye!
If you’re going to be away during the summer, invite friends and neighbours to help themselves to your beans to encourage continued cropping for when you return. Alternatively you could use the break as an opportunity to switch from producing fresh pods to maturing beans for drying. Gluts of the whole fresh pods can be chopped, blanched if you wish (I never do, I can’t tell the difference!) then frozen.
Beautiful, productive, and delicious – what more could a vegetable gardener ask for? Share your runner bean growing tips or favourite varieties with us in the comments section below.