Planting Details Lima beans are a tender annual that grow best in air temperatures between 60° and 70°F. Sow lima beans in the garden 3 to 4 weeks after the average date of the last frost in spring when the soil temperature has warmed to 65° or more for at least 5 days. Start beans indoors as early as 2 or 3 weeks before the average last frost date in spring for transplanting into the garden 3 or 4 weeks after the last frost. Start beans indoors in a biodegradable peat or paper pot that can be set whole into the garden so as not to disturb plant roots. For continuous harvest through the growing season, sow succession crop bush lima beans every two weeks or follow bush lima beans with long-maturing pole lima beans. Beans can continue in the garden until the first frost in fall. Pole lima beans require a long growing period and are not a good choice where the season is short. Lima beans will not set pods in temperatures above 80°F or in cold or wet weather. Time your plantings to avoid hot weather. In mild-winter regions, lima beans can be sown in autumn for winter harvest. Planting and Spacing Sow lima beans 1.5 to 2 in. deep, and plant beans 3 to 6 in. apart; set rows 24 to 30 in. apart. Plant pole lima beans 6 to 10 in. apart; set rows 30 to 36 inches apart. Set poles, stakes, or supports in place at planting time. Pole beans also can be planted in inverted hills—5 or 6 seeds to a hill; space hills 40 in. apart. Thin strong seedlings from 4 to 6 in. apart. Remove weaker seedlings by cutting them off at soil level with scissors being careful not to disturb the roots of other seedlings. Beans can be crowded; they will use each other for support. Soil Grow lima beans in full sun; they will grow in partial shade but the harvest will not be full. Lima beans prefer loose, well-drained soil rich in organic matter. Beans prefer a soil pH of 6.0 to 6.8. Prepare planting beds in advance by working in plenty of aged compost. Avoid planting beans where soil nitrogen is high or where green manure crops have just grown; these beans will produce green foliage but few beans. Watering and Fertilizing Grow lima beans in soil that is evenly moist and well drained. Bean seeds may crack and germinate poorly if the soil moisture is too high at sowing. Do not soak seeds in advance of planting or they may crack; do not over-water after sowing. Keep the soil evenly moist during flowering and pod formation. Rain or overhead irrigation during flowering can cause flowers and small pods to fall off. Once the soil temperature averages greater than 60°F, mulch to conserve moisture. Beans are best fertilized with aged garden compost; they do not require extra nitrogen. Beans set up a mutual exchange with soil microorganisms called nitrogen-fixing bacteria which produce the soil nitrogen beans require. Avoid using green manures or nitrogen-rich fertilizers. Care Large lima bean seed may have trouble pushing through soil that has not been well worked; at sowing, cover the seeds with sand, vermiculite, or a peat moss-vermiculite mix instead. Cultivate around beans carefully to avoid disturbing the shallow root system. Do not handle beans when they are wet; this may spread fungus spores. Set poles, stakes, or trellises in place before planting pole beans. Select supports that are tall enough for the variety being grown. Rotate beans to plots where lettuce, squash, broccoli, brussel sprouts, cabbage, cauliflower, or collards have grown in the past year or two. Disease Beans are susceptible to blight, mosaic, and anthracnose. Plant disease-resistant varieties. Keep the garden clean and free of debris, and avoid handling plants when they are wet so as not to spread fungal spores. Remove diseased plants; put them in a paper bag and throw them away. Beans are susceptible to many soil-borne diseases; rotating beans so that they do not grow in the same location more than every three years will reduce soil-borne diseases. Harvest Bush lima beans will be ready for harvest 60 to 80 days after sowing; pole beans will be ready for harvest 85 to 90 days after harvest. Pick lima beans when pods are plump and firm. Continue to pick pods as soon as they become plump to extend flowering and the production of new pods. When seeds mature, the plant will die. Pods left too long will result in seeds that are tough and mealy. Bush lima beans should produce 2 or 3 pickings in a season.