With beans grown for drying, the pods are allowed to fully ripen and dry out on the plant, then the beans can be stored for use over winter in stews, soups and casseroles. Borlotti beans are a popular choice, and some runner and French beans can also be grown this way.
Leave the pods on the plants to fully mature, then harvest once dry in late summer or early autumn.
Month by Month
Most beans grown for drying are climbers, as these are more productive. Dwarf varieties can be used too, but produce smaller crops. They also don’t dry well on the plants, as the pods often touch the ground, where they get damp and easily rot, so they are best picked and dried indoors.
Borlotti beans are the best-known beans for drying, but most runner and French beans can be grown in this way, although certain varieties are particularly suitable. Different varieties produce dried beans of various colours, including white, brown and purple. Others beans specifically for drying include the striking black and white ‘Yin Yang’ beans.
When choosing varieties, look in particular for those with an RHS Award of Garden Merit (AGM), which shows they performed well in trials – see our list of AGM fruit and veg.
What and where to buy
You can buy suitable bean seeds in garden centres and from online retailers. Many also sell young runner and French bean plants in spring and early summer, which are useful if you only want to grow a few.
Preparing the Ground
Choose a warm, open, sunny growing site, ideally on light, free-draining soil.
Weed thoroughly, then fork in lots of well-rotted manure or garden compost – at least two bucketfuls per square metre/yard. Ideally do this a few weeks ahead of sowing or planting out, to allow the ground to settle, or even better, do it the previous autumn if you’ve planned your growing site early enough.
You can also add a high potassium general fertiliser, such as Vitax Q4, at a rate of two handfuls per square metre/yard.
Because beans take longer to mature fully, it’s essential, especially in northern regions, to sow them early, ideally indoors. Borlotti, runner and French beans are tender plants that won’t survive frost, so wait until after the last frost before sowing or planting outside. Choose a sunny growing site, and prepare it beforehand by adding well-rotted manure or garden compost and putting up supports for climbing varieties.
Keep them on a sunny windowsill, in a propagator or in a greenhouse at over 12°C (54°F). Seedlings will grow rapidly and need watering regularly.
The young plants can be transplanted outside once there is no danger of frost in your region, usually in late May or early June – see Planting out, below.
Bean seeds need warmth to germinate, so wait until your soil has reached 12°C (54°F) – usually by mid-May in the south of the UK, and two weeks later in the north. If your soil is heavy and wet, pre-warm it in early spring by covering with clear plastic sheeting or cloches for about four weeks before sowing.
Sow the large seeds individually 5cm (2in) deep – one or two at the base of each bamboo cane, later thinning to one seedling per cane, and protect from slugs and snails.
With dwarf beans, sow seeds 10cm (4in) apart, in rows 45cm (18in) apart. Sow a few extra at the end of the rows to fill any gaps if some seeds don’t germinate. You can also sow these through weed-suppressing membrane to reduce the need for weeding and prevent the pods being damaged by contact with the soil.
Putting up supports
To make a double row of A-frames, insert 2.5m (8ft) bamboo canes 15–30cm (6–12in) apart, with 45–60cm (18in–2ft) between the two rows. Slope them inwards and tie each pair near the top, then add a horizontal cane to link them all together and increase stability.
For X-frames, slope the canes at a sharper angle so they cross in the middle. Tie them at the centre, and add a horizontal cane for stability. An X-frame takes up more space, but picking is easier as the beans are within reach and cropping is usually better.
To make a wigwam, again use 2.5m (8ft) canes, four or five per wigwam, spacing them 15–30cm (6–12in) apart at the base. Tie the tops of the canes together.
Wait until after the last frost before planting indoor-raised or bought young plants outside. Harden off to acclimatise them to outdoor conditions for a couple of weeks, by putting them either in a cold frame or in a warm, sheltered spot, covered with fleece or cloches.
Make sure your planting site is ready – see Preparing the ground and Putting up supports above.
Plant one climbing bean at the base of each bamboo cane, then tie their stems loosely to the canes to get them started. With dwarf beans, space plants 30cm (1ft) apart.
Beans are thirsty plants so water regularly, especially once they start to flower and form pods.
Spread a thick mulch of garden compost around the plants to help hold moisture in the soil and deter weed germination.
Why add mulch? An organic mulch, such as garden compost or well-rooted manure, is a great way to add nutrients and valuable micro-organisms to your soil. It also holds in moisture and deters weeds.
Pruning and Training
Once climbing beans reach the top of their supports, cut off any additional growth. This should encourage side-shoots lower down, keep the crop within reach and help to stop plants becoming top-heavy.
Tie in any stems that come loose from the canes in windy weather.
Beans start to mature from July onwards, from early sowings.
When ready to harvest, the pods become dry, shrivelled and brittle. Avoid picking after rain, so the beans are as dry as possible.
Remove the beans from the pods and lay them on a tray in a warm place to fully dry out and turn hard. Then store in airtight jars and use in casseroles, soups and stews.
Harvest the last of your crop before the first frost. If any pods aren’t fully mature, then pick, shell and freeze the almost-mature beans, for use as you would dried ones.
These beans are easy to grow, but they are tender, so must be kept indoors until after the last frost. If a late cold snap is forecast, cover your plants overnight with cloches or fleece.
Seedlings and young plants are vulnerable to slugs and snails – see our tips on how to stop slugs and snails. Keep watch for black aphids on the shoot tips and under leaves – squash them or wash them off with a jet from the hose before they get established.
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