Container Gardening: How to Grow Beans in Pots
Green beans can be beautiful plants for pots. With their pretty flowers and attractive foliage they can be a real asset on a sheltered patio, balcony or in a courtyard setting.
There are climbing and bush forms of green beans which include scarlet runners and haricot or French beans; all are possibilities for containers.
Beans need warm temperatures to germinate and grow, so you can sow them much later than many other vegetables. It’s never worth starting before late spring if sowing outdoors. In colder areas start them indoors and plant out after danger of frost has passed.
Climbing beans, especially scarlet runners, need a situation sheltered from wind. When they have covered the canes or supports the luxuriant foliage offers considerable wind resistance; even large containers can be blown over.
Runner beans need a few hours sun a day, but are more tolerant of some shade than many vegetables. In fact some shade at midday can be advantage in preventing wilting. Haricot or French beans do best in an open sunny position.
Sowing the seed
Beans dislike cold and are killed by frost, so start the seeds in pots indoors and plant out in late spring or early summer. Scarlet runner bean seeds can be sown individually in 9cm (3”) pots or in root trainers.
Haricot beans can be sown two or three seeds to each pot. Sow about three weeks before you want to plant out. This will produce substantial, well-rooted plants that will get off to a flying start when planted out.
Climbing beans need a large container, deep enough to support canes or other framework used to grow them up. A half barrel filled with multi-purpose growing media with added loam is ideal.
A container that is 75cm ( 30”) in diameter would support eight or nine plants growing up a simple wigwam of canes.
Although climbing beans can be grown in grow-bags this is rarely ideal. The small volume of compost means that it is difficult to keep them watered when fully grown; supporting the plants is a challenge. If you want to use grow bags then choose bush haricot beans.
The climbing varieties of round podded haricot beans are lighter in growth habit and can be grown in smaller containers; a large pot 45cm (18”) in diameter is ideal for eight plants.
Their twining stems work well when grown up the curly metal plant supports originally developed for tomatoes. These are available in a range of colours and are a feature on the patio, even before the beans advance up them.
There are bush varieties of scarlet runner beans as well as haricot or French beans. These can be grown in smaller pots, troughs or vegetable growing containers. They can even be grown in window boxes or balcony troughs.
They can also be combined with other vegetables such as cut-and-come-again lettuce or bushy, trailing tomatoes.
Watering is critical at the flower production stage. If the plants dry out the buds drop. In warm weather, when the plants are in full growth and flower; they enjoy being sprayed with water over leaves and flowers in early morning or evening. This also helps with pollination.
There are plenty of varieties to choose from, old and new. It is probably best to choose a red or bicoloured flowering variety of runner bean for pots as these are prettier.
‘Red Rum’ is a popular choice because it is self-fertile and less dependent on pollinating insects. ‘Painted Lady’ is one of the most attractive with red and white showy flowers.
The bush runner bean ‘Hestia’ is deservedly popular for patio pots. It is free-flowering and showy with red and pink flowers and a plentiful crop of beans.
The climbing haricot bean ‘Blue Lake’ is unbeatable for flavour, and is a good choice if picking is going to be irregular at any time in midsummer. The succulent pods are stringless and do no go tough with age. Its flowers are insignificant and the beans seem to appear from nowhere, so keep an eye open for them.
Of the bush French Beans ‘Purple Queen’ is very attractive with dark green leaves and tiny purple flowers followed by a heavy crop of delicious purple beans. The only disappointment is that they go dark green when cooked.
‘Mont d’Or’ has flattened succulent pods of soft yellow. They are delicious cooked and served cold with vinaigrette dressing. These yellow beans are often called wax beans.
Whichever type of bean you grow pick them when the pods are young and tender. It is unlikely that you are trying to grow the longest pods for competition so pick for flavour and quality. Scarlet runner beans should be around 20cm ( 8”) long and snap without obvious strings. French beans should be around 15cm (6”) long, smooth and not bulging with seeds.
Climbing beans can be combined with lighter growing sweet peas such as the old-fashioned ‘Cupani’ to make them even more attractive. The scarlet blooms of a red-flowered bean make a striking combination with the rich purple flowers of the sweet pea.
A few nasturtiums or calendulas can be sown around the base of the beans to add colour around the top of the container.