Growing beans

Beans are among the most nutritious of the vegetables we grow and eat. They are good for the soil; their roots harbour bacteria that add nitrogen to the soil, harvested from the air. They, and peas, are the only crops to do this.

In this country we tend only to grow three main types of beans – broad beans, runner beans and French beans. All three are derived from different wild species and need different treatment if they are to do well but all are easy when you understand them.

April and May are the time to get them all started so make sure you get a bumper crop this year with these simple tips.

Broad beans are the hardiest beans. Many gardeners start their bean-sowing year in October and November with ‘Aquadulce’, often covering the small seedlings with cloches in the coldest months. On many soils the seedlings struggle and a spring sowing in March or early April soon almost catches up and is less worry.
Broad beans will grow in most soils. You can start them in individual pots in the greenhouse but they grow well when sown in the ground now.
Sow the seeds about 15cm (6in) apart in double rows 45cm (18in) apart. Plants usually need some support as they grow. Canes stuck in the ground with string around is usually enough. Once the seedlings appear you may see round notches missing around the leaves. This is caused by pea and bean weevil and it is usually not a significant problem.
Soon the plants will be growing fast and will be in flower. Blackfly is the next problem – you can either spray with a contact insecticide (chemical or organic) or try and rub them off with your fingers. Pinch out the shoot tips above the top cluster of flowers and,
if these are not covered in bugs, boil them for a tasty green vegetable.
You then have a choice of when to harvest your pods. Some say they are tasty when picked very small and eaten whole but the insides are so woolly that I have never quite fancied that. On the other hand, do not wait until the pods are large and the beans inside as tough as conkers and covered in skins that need a Swiss Army knife to take off. Pick them young and they are delicious.
Broad beans take up a lot of space for the size of the crop so I don’t recommend them for patio containers.

French beans
These come in two versions, climbing and dwarf. The climbing French beans are useful where runner beans rarely set well because they are self-fertile. They all prefer moist, rich, warm soil and are good for containers. The most popular are the ‘pencil-podded’ types which are the supermarket ‘Kenya’ beans, which tend to be stringless and tender. Flat-podded types such as ‘The Prince’ are good too but can get stringy as the beans age. Look out for purple and yellow varieties too. Climbing French beans may be more work because they need support but they crop for a longer period.
All these beans, if left so the pods go dry, turn into haricot beans which can be eaten. Some varieties, usually those that are less tender when young, are grown especially for this.
French beans hate cold, wet soil and the biggest cause of failure is sowing outside too early. Wait till late April and continue into May and even June with your sowings.

Runner beans
Runners are hugely popular but they often fail to set pods. This can be due to cold weather, extreme heat, dryness or sparrows pecking at the flowers. If you have these troubles, try white-flowered runners (right) – they are usually more reliable.
Like French beans, runners dislike cold conditions so either sow them this month in cell trays in the greenhouse or outside next month.
White-flowered runner beans Runner beans love warmth, moisture and lots
of organic matter in the soil so treat them to garden compost, rotted manure and mulch with grass cuttings as they grow. It is not unusual for the early flowers not to set but, as the days get shorter, they usually get into their stride and do better.