What Is the Growth Rate of a Bean Plant?

Growth Requirements

• To grow well, most beans need moderately warm soil and a pH of 6.0 to 6.5. Since beans are nitrogen-fixers, they should only require fertilizer early in life. Add nitrogen-rich fertilizer to the soil at planting time, and again in two weeks if foliage appears pale green in color. Lack of nitrogen may slow down vegetative growth. Inoculating the soil prior to planting may help the plants obtain the bacteria they need to fix nitrogen.

Growth Rate

• Beans go through a long stage of vegetative growth before producing blossoms and directing energy into bean production. Pinto beans, which grow similarly to other beans, devote the first four to eight days to germination. Once seedlings emerge, they grow vegetatively for 28 to 32 days. 32 to 40 days after planting is the third stage of flower and pod production. For the next two weeks, the pods grow and eventually produce seeds to be harvested day 60 and later.

Accelerating Growth

• Warmth and moderate moisture are key to quick and vigorous bean growth. To speed germination, plant beans in soil that is 75 to 85 F. The best air temperature for growth is between 70 to 80 F. Providing nitrogen to bean plants can increase growth rate and plant size, but may detract from fruit quality. Bean roots are often 2 feet deep and can absorb moisture well; apply mulch around roots but avoid watering too often.

Harvest

• Proper harvest method and scheduling ensure productive plants and tasty pods. Most varieties of pole and bush beans reach their full height of 2 to 3 feet and produce edible beans in 60 to 75 days. Snap beans can be harvested in 50 to 60 days because they are picked before seeds are ripe. Pole lima beans take 60 to 110 days, and bush lima beans take about 65 to 75 days. Harvest lima beans when pods are plump but before seeds harden. Pick snap beans once pods are mature, but while seeds are still small. Continuous picking every three to four days will maximize yield and help ensure pods do not over-ripen.