Dwarf French Beans are a compact habit plant that don't need staking like runner beans or peas. They are easy to grow and withstand dry conditions perhaps better than any other crop, and they leave the soil in very good if not better condition after cropping because of the nitrogen built up on the roots. French beans are picked when they are young and green, the beans are not removed but the complete pod cooked and eaten.
French beans prefer light soil, but can be grown in heavy clay soil if enough fine organic matter is forked in. During the Autumn or Winter dig in old compost or well rotted manure at one bucketful to the square meter. Leave the ground rough during the Winter to let the cold winds and frosts get to it. In the spring give the soil a light forking and add some organic fertilizer.
French Bean seed should never be sown if the soil is wet and cold - never pour water in the drill at sowing time. For an early crop of French beans – sow under cloches.
Start in late March or early April for a harvest in June by sowing seeds in boxes of potting compost in a cold frame 5cm (2in) apart and 5cm deep.
Gradually introduce the seedlings to colder climates by raising the frame light to allow air circulation and leave off completely on fine warm days.
Transplant the French bean seedlings towards the end of May, 22.5cm (9in) between plants and rows 45.5cm (18in) apart.
Sow French beans towards the end of May in 7cm 6 cell modules. Plant one seed per module about 4cm deep. Use a fine seed compost. Water and leave in the greenhouse or polytunnel to germinate. There should be no need for a heat bench or propagator this time of year. The seeds should germinate in 7 - 14 days and will grow quickly.
Plants that have been raised indoors will need to get used to the outdoor temperature and conditions before they can be planted outside, this will take about a week to 10 days depending on the weather. French beans hate the cold and are likely to suffer shock so make sure you do this. The best way is to use a cloche or mini greenhouse. You can leave the cloche off the plants on dry frost free days and replace at night. Gradually increase the time with the cloche removed until the end of the week when you leave it off day and night. If the weather is mild you may not need the cloche, just move the plants outside for longer periods each day. If you have started your seeds on a windowsill you will need to leave them in an unheated room for a day or two before moving outside to the cloche.
French beans can be direct sown outside towards the end of May. It is possible to start them off earlier if you have a more southerly garden, I'm keeping on the safe side. Sow beans 4cm deep with a spacing of 15cm between plants and 40cm between rows. Slugs Slugs can be a major problem when seedlings are small. Use an organic slug pellet or use a beer trap for control.
Put cloches in place two weeks before sowing to warm up the ground. About the last week in April put out a line of string as a guide and form a V-shaped drill 5cm (2in) deep with the hoe.
Sow the French beans seed 15cm (6in) apart and then rake the soil back over lightly to cover the beans completely.
Firm the soil down with the flat part of the hoe - this sowing should be ready in early July.
Sow the next crop in May without glass. For a succession of crops and regular picking of beans you will need to sow a row of French beans every three weeks from April to the middle of July.
If you want to discover the best cropping powers and flavour for your particular garden try sowing a different variety each time.
It can be sometimes necessary to water under cloches when the plants are 15cm (6in) high. In early October, cover the mid-July sowings with cloches again to protect the French beans from frosts. This way it is possible to pick French beans until the second week of November.
One you've hardened off your bean seedlings they are ready to be planted out in the garden. Choose a warm sheltered as French Beans hate exposed sites. Plant in rows with 15cm between plants and 40cm between rows.
Keep the area around the seedlings weed free and aerated with regular hoeing. An oscillating hoe is the easiest and most satisfying tool for hand weeding.
Keep an eye out for slugs as they can ruin all your hard work in no time. Use an organic slug bait or beer trap.
Apparently slugs love bran so leaving bran piles around the garden will attract them in their droves. You can collect them and throw them over your neighbour's wall. It is said they gorge themselves so much they explode but I can't say I've ever witnessed this particular spectacle.
When the French Bean plants are about 10cm (4in). high, thin them to (22.5cm (9in) apart.
When the pods are formed you can help a little by pushing in some twiggy sticks to keep the plants upright and prevent the beans from trailing on the ground - but normally French beans will stand upright of their own accord.
Supporting the French beans also keeps them clean and lessens the possible threat of damage by slugs. So you could put bamboo canes at both ends of each row and tie some string between them to help keep them upright. Hoe lightly between the rows to keep down the weeds. When you do this, draw the soil up to the plant rather than away.
Slugs as they can ruin all your bean plants in no time. Use an organic slug bait or beer trap.
Black bean aphid (Blackfly) can be problem in July and August. You can spray with the natural insecticide 'Pyrethrum' or wash off with a strong jet of water. Growing marigolds near beans can help as they attract beneficial insects like ladybirds who love to eat blackfly.
Downy Mildew and foot rot can be a problem but with good crop rotation this can easily be controlled.
Regular picking will encourage more pod formation and produce a bigger crop. Always pick young and tender pods. If you leave them to grow more than 10cm (4in) they become tough. Hold the stem and pull the pod in a downwards direction to avoid damage and uprooting when picking French beans. You can harvest your french Beans from July until the first frost. It's important to pick your pods regularly (at least once or twice a week) to get the tenderest beans. Many people are put off runner and French beans from eating beans which have grown too big and stringy.
If you don't keep harvesting the plant will put all its energy into ripening the seeds rather than producing fresh, new beans for you to eat. Even if you can't face another bean keep picking otherwise the plant will stop producing for the season. If you let just one or two beans ripen the plant will shut down production. You will have a glut of beans at some stage so read up on how to store them, give them away, compost them, whatever, just keep picking!
If you want dried beans (haricot) for the winter, leave a few plants to ripen and at the end of the summer cut them at ground level. Hang the beans to dry upside down in the sun (cover in bad weather). When the French bean pods are absolutely crisp and dry, shell them and store in airtight containers.