How to grow a lean green French bean As the season was fairly dry at the test site in Gloucestershire, the trial was watered regularly. The plots were weeded regularly by hoe and by hand. Pods were picked weekly from early August to mid September. Some varieties were affected by a leaf-spot disease which spoiled the pods following heavy rain in late August. Best buys Amethyst The heaviest cropper on tall, vigorous plants that could have done with some support. The pink flowers were attractive and the dark purple pods were very easy to pick, held fairly high on the plants. Amethyst" had the longest cropping period, from early August to mid September. The pods were not particularly attractive, rather knobbly with prominent beans, but for quantity and novelty value they take some beating. They turn dark green on cooking but have a very strong beany flavour. Best for biggest and longest crop Yield from 40 plants 5.8kg (12.8lb) Stanley Stanley" gave the second-biggest crop overall, most of it in mid August, so it is a good choice for bulk freezing. It was the best of the green-podded varieties trialled, and very similar to the kind you buy in the supermarket. The plants were of average size and stood well without support. The creamy yellow flowers turned into mid-green pods that were 6in/13cm long with a pronounced hook. They were easy to pick, even though they were held quite low down on the plants, and had a mild flavour. Best for green pods Yield from 40 plants 4.6kg (10.1lb) Golddukat Golddukat" gave a good crop of pale yellow pods for most of August. The plants were of average size, 12in/30cm high and 2in/5cm wide, with creamy yellow flowers. The fleshy pods were up to 6in/15cm long and good quality, despite having fairly prominent beans. They were held high on the plants and therefore very easy to pick. Cooked, they had a soft texture, were sweet and only slightly beany flavoured. Best for flavour Green Arrow Green Arrow" gave good yields of supermarket-quality green beans. The plants were an average size with plenty of vigour. They started cropping early but continued steadily until the end of August. The white flowers turned into mid-green pods which were held low down but were fairly easy to pick. They were typically 6in/13cm long and fleshy, with a pleasant texture and mild flavour. Best for easy to pick Yield from 40 plants 4.3kg (9.5lb) Sonesta Another interesting yellow-podded bean. Sonesta" cropped from early August to mid September, with a peak in mid to late August. The plants were a typical 12in/30cm tall and 22in/55cm across and bore white flowers. The lemon yellow pods were easy to pick. They weren't the most attractive, as the beans inside were rather prominent, but they had a sweet, almost nutty flavour. Unlike the purple varieties, yellow beans do retain their colour when they're lightly cooked. Best for tasty yellow pods Yield from 40 plants 4.2kg (9.3lb) More beans to try For haricot beans, try the Italian 'Borlotti. It's available as both dwarf and climbing versions. Grow your own kidney beans. Leave the pods to dry on the variety 'Canadian Wonder" and you'll end up with red beans. Try some interesting heritage varieties such as 'Ying Yang" (black and white) and 'Pea Bean" (red and white). How to grow From June onwards, sow direct into seed drills about 0.5in/1.5cm deep and 12in/30cm apart. An alternative is to sow double rows 6in/15cm apart for easy picking. French beans are very sensitive to frost - don't sow early or late in the season, except in the greenhouse. You can get a head start by sowing the seed in pots to plant out after the last frost in your area, usually late May to early June. Alternatively, it's easy to grow dwarf beans in pots. Reckon on about four plants to a 12in/30cm container. Sow more seed than you need, to allow for failures and pests. When the seedlings emerge, thin to roughly 3in/7.5cm apart and if necessary transplant any spares to fill gaps. The plants shouldn't need support, but in exposed gardens use a few twiggy sticks or hammer stakes into the corners of the plot and run string round. Plants shouldn't get much more than 12in/30cm tall. When the first flowers appear, a really good soaking each week should improve yields of pods in a dry summer. Pick pods of the slim varieties when they reach about 6in/15cm long and before the beans start to show. Nip them off with finger and thumb; pulling too hard may yank the whole plant out of the ground. As the pods crop over a fairly short period, make a couple of sowings through the summer, the last in July, to allow them to crop before the first frost. If you want to save seeds, leave the best plant unpicked until the beans rattle in the pods. Dry them indoors and label them for sowing the following year. Where to buy DT Brown (0845 371 0532; dtbrownseeds.co.uk) Dobies (0844 701 7625; dobies.co.uk) Marshalls (0844 557 6700; marshalls-seeds.co.uk) Mr Fothergill's (0845 371 0518; mr-fothergills.co.uk) Plants of Distinction (0844 856 0763; plantsofdistinction.co.uk) Thompson & Morgan (0844 248 5383; thompson-morgan.com) Unwins (01480 443395; unwins.co.uk)