Butter beans, also known as lima beans, can be a delicious addition to a garden. Fresh butter beans are excellent boiled and buttered, put into a salad, or in any of a large variety of recipes. There are many varieties, including both pole-climbing beans and bush beans. They should be planted two to four weeks after the average last frost date of the spring and after the soil temperature has risen to 18.3 degrees C (65 degrees F). Butter beans can be planted every two weeks in order to ensure a constant supply of beans.
Find a butter bean variety that suits your needs. You may want to avoid the hassle of setting up poles for the beans to climb, or you may want the space efficiency that pole beans provide. Something else to consider is that pole beans require a longer time to grow and therefore will not do as well in climates with short growing seasons. Either way, if you want large butter beans, be sure to get a large-seeded variety such as Fordhook Improved or Excel Northern Fresh.
Locate a site in your garden with full sun and rich, well-drained soil, and work the soil to loosen it. If you need to improve the soil's richness, add generous amounts of organic matter such as compost or peat moss. Add a little sand (one part sand to nine parts other soil) if the soil does not drain well. A soil pH of 6.0 to 6.8 is optimal for bean plants.
Sow the butter beans 2.5 to 5 cm (1 to 2 inches) deep and 7.5 to 15 cm (3 to 6 inches) apart in rows. Allow a distance of 45 to 60 cm (18 to 24) inches between each row, if you are planting bush beans. Keep pole bean rows 60 to 90 cm (2 to 3 feet) apart.
Set trellises, poles or other supports in place at this time if you are planting pole beans.
Water regularly and evenly, but do not allow the soil to get too wet. Keep weeds away from the beans, but be careful when pulling them out of the ground by their roots. They may entangle with and damage the beans' root systems.
Fertilise with aged compost if necessary. Avoid using green manure or fertilisers high in nitrogen.
Harvest the beans when they are ripe. This should be about 60 to 80 days after planting for bush beans, and 85 to 90 days for pole beans. Pick the beans whenever the pods appear to be firm and plump.
Examine the beans regularly for aphids, mites, leafhoppers or insect eggs, and remove them.
Avoid handling the plants when they are wet, as this can spread fungal diseases. Remove and dispose of any infected plants. Avoid planting beans with beets, kohlrabi or onions.