What Kind of Soil Is the Best for Bush Beans?

Soil pH

• Bush beans grow in a variety of soil types, but the best soil for growing this crop is a slightly acidic pH of 5.8 to 6.3. This provides the optimum environment for the roots to use nutrients in the soil.

Soil Temperature

• Beans germinate well when the soil temperature is around 60 degrees Fahrenheit. This is the best temperature to ensure healthy seedlings with vigorous growth. When the temperature is below 50 F, seeds can crack, allowing the introduction of microbes that can harm the growing plant. You can use a thermometer to determine whether the temperature of the soil is warm enough for planting bush beans.

Soil Moisture

• Seeds of most bean plants crack and germinate poorly if the moisture in the soil is too great. Do not soak beans before planting. Plant the seeds in dry soil just before a rainy period. Water the seeds just after planting. Good drainage is essential for good bean production. A mixture of sandy, loamy and silty soil is best. Beans are shallow-rooted plants so you may need to add an amendment to clay soil to loosen it for the root system growth. Add compost to soil to aid soil aeration and water retention, and your bean plants will thrive. Coco fiber, called coir, is another good soil amendment for beans.

Soil Diseases

• Soil fungus can be a problem for bush beans because these contaminants are often present in most types of garden soil. It is when the amount of fungus in the soil builds to a high level that plants begin to fade. Rhizoctonia solani is a type of fungus that causes root rot in bean plants. It generally does little harm unless the plants are weakened by other conditions, such as a virus condition or insect infestation. Fusarium solani f. phaseoli grows in warm soils and so can affect bean plants later in the summer with yellowing, brown lesions and taproot rot. Phythium spp. causes rot of young seedlings. Plant experts recommend a rotation of four to five years between bean crops to help prevent these diseases. Cool soils tend to increase the incidence of root rot diseases. Fungicide sprays can help these conditions.