Warm Season Beans
Beans belong to a group of plants called legumes. Legumes are members of the Fabaceae plant family grown mostly for their fruits which are produced as pods. Usually the pods are picked before the seeds inside have fully matured. For green beans, the whole pod is picked and consumed. With broad beans the immature seeds are removed from the pods and eaten. Sometimes beans are left to mature and dry in the pods, in which case the hardened bean seed is known as a ‘pulse’. Examples of beans grown as pulses include butter beans (lima beans), kidney beans, and mung beans. However, sometimes broad beans are also grown as pulses, particularly horse beans which is a name given to some varieties with smaller bean seeds.
For the home vegetable garden, the most widely grown beans are usually common (green) beans, runner beans, and broad beans. The common bean is known by a number of other names including green beans, French beans, haricot beans, flageolet, and string beans. They are all cultivars of Phaseolus vulgaris. Most green beans have a compact or bushy growth habit and are referred to as ‘bush beans’, or sometimes ‘dwarf beans’. Some cultivars have a climbing habit and are known as pole beans.
Common beans Phaseolus vulgaris are warm season crops. They grow well in temperatures from around 15°C through to 29°C, depending on the cultivar. Some to try are as follows.
- Bush types: Blue Lake Bush, Provider, Cherokee Wax (yellow seed pods), Windsor Long Pod, Valdor (yellow seed pods)
- Pole types: Purple King (purple seed pods), Kentucky Wonder, Kentucky Blue, Blue Lake Pole, Vitalis, Westralia
Planting
For the best crops, it is as well to prepare the soil beforehand by digging in some well-rotted manure. Another option is to sow the seed in a row directly in the ground. Then dig a shallow trench either side about 6cm away and place fertiliser in these. The roots of the beans will eventually reach the fertiliser when they are growing at their most vigorous. You can also grow beans in containers provided you have enough depth. You are going to want at least 30cm to allow for good root growth. Seeds should be sown singly, at a spacing of 10cm between seeds. You can always plant a couple of seeds close together and thin out where necessary.
Watering & Feeding
Beans need plenty of moisture, but you should never let them become waterlogged. A regular supply of nutrients will result in rapid growth and early cropping. In particular, provide a feed with liquid fertiliser when the first fruits appear.
Phosphorus, potassium, and sulphur levels need to be high, but nitrogen levels should not be as high as with other vegetables. The ratio of nitrogen to potassium should be roughly equal. They are sensitive to excessive boron so be careful not to overfeed with this nutrient.
