Runner beans are one of Britain’s favourite garden vegetables, as they are easy to grow and produce a lovely big crop. Ideally you need a nice, sheltered site with plenty of sun and well-drained soil, but beans are forgiving plants and will put up with a lot. If you have a small garden you can even grow them in pots!
Runner beans like a rich soil, so before you start growing you should prepare a plot. Beans need canes to support them, so decide whether you are going to grow your beans in a row, or in a circle supported by a wigwam of canes. Once you’ve decided on a plot, dig it over well and add plenty of well-rotted manure, leaf mould or home-made compost.
If you are growing your beans in a pot, make sure it is a large pot with a diameter at least 45cm (18”). Fill the pot with a mixture of half loam-based and half loam-free compost.
Before you plant your beans out you’ll need to set up support canes for them. The method most used is to grow them in a double row (the 2 rows should be 18in apart) up inwardly sloping 8ft (2.4m) tall canes. If you slope the canes so that they meet roughly 2/3rds of the way up the cane and tie them here, it will make picking easier and the yield will generally be better too. For stability, it's also good to place and tie in a cane horizontally where the crossed canes meet. If you are growing the beans in a circle, create a wigwam of canes by driving them into the ground in a circle, then tying all the tops together in the middle. Canes should be 2.4m (8 ft) long and should be placed 15cm (6”) apart. If you are growing in rows, space the rows about 60cm (23”) apart.
Growing From Seed
You can grow runner beans from seed in a greenhouse or on a sunny windowsill. Late April is about the right time to start growing. Fill a number of 3” plant pots with compost, allowing for a few that may not grow. Place one seed in each pot, about 4cm (1 1/2%”) deep. Water well, and keep watering every few days to keep the soil damp.
Your seedlings should be ready to plant out after about three weeks. Harden them off by putting them in a cold frame or cool porch for a few days, or if you don’t have one, put them outside during the day but move back indoors at night. Once the plants have adjusted to the outdoor temperature, you can plant them out. Dig a hole next to a cane, large enough to fit the pot into. Gently tap the plant out of the pot, tease the roots free slightly and place the young plant in the hole. Press the earth in gently around the plant, and water well.
If you missed the window for growing your own plants from seed, you can often buy plants from garden centres, or you can try growing from seed outdoors. To grow seeds outdoors, you will need to plant them where they are to grow, any time from mid May. Plant two seeds, 2.5cm (1”) deep, next to each cane. If both seeds grow, remove the smaller of the two plants.
Your beans may need some encouragement to start wrapping themselves around the canes. Beans prefer to wind themselves in an anti-clockwise direction, so bear that in mind. If you try wrapping them around clockwise they are likely to unwrap themselves! When they're first starting out, you can tie them in to the canes loosely with garden string to help them along.
Runner beans need loads of water particularly once the beans start to grow. Add some mulch around the bottoms of the plants to help keep moisture in, and give them a really heavy water at least twice a week. Water in the early morning or late evening, so that the plants make the most of the water rather than it being burnt off by the sun.
Pick the beans regularly once they are large enough – the more you pick, the more the plants will produce! If you have too many, don’t leave them on the plant otherwise they will become tough and inedible, as well as stopping more from growing. Give unwanted beans to friends or neighbours, or freeze them to use in the winter.
You may find that the plants get invaded by blackfly – if this happens, wash them off with soapy water.
Once the plants reach the top of the canes, pick off the tops. This will encourage fruiting rather than growing.
All project content written and produced by Mike Edwards