If restricted to just five veg to grow at home, French beans would always be among them. French beans are easy to grow, easy to pick, easy to prepare for the pot and very tasty. There are a few issues that must be remembered but basically they are simple to grow.
You have lots of choices. The main one is whether to grow dwarf or climbing kinds. Of the two, dwarf beans tend to crop more quickly from sowing, crop over a shorter period and the beans are mostly thin and round – like pencils – though some have flat pods. Most are green but you can get purple and yellow pods. Some have speckled pods but more of that later.
Climbing beans grow to 2m or more and crop over a longer period, as they twine. You can get them with thin pods but also flat pods which are rather like bumpy runner beans. The advantage of French beans over runners is that the flowers are self-fertile so you do not get the pollination problems that make runners such a hassle in August, when night temperatures can be too high to allow pods to form.
The wonderful thing about French beans is that the seeds are edible. So if you don’t pick the pods when tender you can leave them till they get tough and eat the seeds. They can be eaten while the pods are still soft, when they can be cooked simply by quick boiling or you can let the pods dry and save the dried seeds for use. I don’t trust my drying skills so I boil and freeze them immediately after picking so I can add a few, on a whim, to stews and soups. The speckled, often Italian, varieties are grown for dried beans and there is a whole class of drying beans, and I am trying a new one this year, that are fun to try. If you are ‘into’ heirloom growing, these are the ones to grow up your maize, beside your squash, in the ‘three sisters’ combination.
French beans, like other beans, fix nitrogen from the air and enrich the soil (for a short time). They tolerate lime but need a well-drained, warm soil, ideally well dug and full of organic matter.
The most common problem with French beans is poor germination. But this is not inevitable. It is just that they hate wet, cold soil. I would not sow outside here until May. Then I can sow again in June for a late crop. You can get a head start by sowing in cell trays or pots in late March or April but remember that if planted out and the weather is cold in May the plants may suffer. They are useful for polytunnels and I grew mine in there last year because the beds were not ready outside and 20 plants kept us supplied.
Use small pots and fresh multipurpose compost and sow two beans per pot. Plant them out 20-25cm apart in rows 45cm apart. Climbing beans should be planted at the base of canes or strings 25cm apart. They do well in a large patio pot and they are not unattractive, with lilac or white flowers. Pop in a few sweet peas for extra interest but avoid anything too boisterous, such as nasturtiums.
All French beans are tasty and some may be stronger in flavour than others. Most of the purples go green when cooked but the yellow ones stay yellow. I think that the texture of the yellow is more waxy than the greens and I like them. All are squeaky if cooked lightly. The big advantage of the yellows and purples is that they are easy to find when picking. Do pick carefully so you do not damage the plants – don’t just grab and pull.
Wait for warmth
The seeds will rot in the ground if it is cold and wet. Wait for good weather if sowing outside. Otherwise sow on the windowsill two to three weeks before you can plant them out.
Try coloured beans
French beans are available all year in their green form. Apart from the satisfaction of growing your own, try something that you can’t buy in the shops.
Use at every stage
Don’t despair if you miss some beans and they have gone stringy. Just take out the seeds and cook these – nothing need go to waste.
Dwarf beans crop heavily but for a relatively short time (a month or so) so sow every month from May to early July. Ideally sow an early variety for late sowings. Yes, you read that right! Early varieties are so called because they crop quickly after sowing and they are just what you need for a July sowing – to crop quickly before autumn.