Beans, as a category, encompass a wide variety of legumes. Beans produce pods with seeds inside them. Both the immature pods and the seeds are utilized in cooking, and it’s the stage of growth that determines a pod, a shelled bean, or a dried bean, not the specific type of bean. Beans come in compact bush-type plants and vining pole varieties.
From green beans to yellow wax beans, from lima beans to unique heirloom varieties such as Jacob’s Cattle or the Tiger’s Eye, there is a variety of bean for any palette and any dish. Beans are easy to grow, making them an excellent choice for the first-time gardener.
Sandy loam and silty loam soils are best for growing beans in, although they will grow in most any dirt except that with a high clay content. Clay soil is poorly drained and encourages root rot and blossom drop in the plants. Beans grow best in soil with a neutral pH, but they can tolerate pH levels anywhere from 5.5 to 7.5. For best yields, you should amend the soil to compensate for pH levels and type. Beans produce some of their own nitrogen, but it’s advised that you grow a green manure crop the previous fall and turn into the soil in spring in preparation for your garden.
When to Plant
Beans are a warm season crop that should be planted in full sun after all danger of frost is past. They do best in soil temperatures of about 60 to 70 degrees F. The only exceptions to this rule are broad beans (fava beans). Broad beans need to be sown early, while the soil is still cold and as soon as it can be worked. In mild winter areas, sow broad beans in the fall for a winter harvest.
How to Plant
Direct seed your bean seeds in the garden, spacing them 1 to 2 inches apart and 1 inch deep. Crops tend to mature at once (which can be overwhelming), so succession planting is recommended. Sow your beans about every two weeks and stop about 60 days before the first expected frost date. For those beans sown later, when the soil is hot and dry, plant beans 2 inches deep.
Thin your seedlings out, but don’t try to get exact spacing. Instead, thin out weak, spindly plants and only keep the vigorous healthy growers. Weak plants are prone to disease which can quickly spread to your entire crop.
Be very conservative in fertilizing your plants. Too much fertilizer will encourage plant growth at the expense of producing pods. If you’re concerned about the nutrient levels in your garden, apply a foliar spray such as Protogrow®.
Pods are ready for harvest when the tips are flexible and bend without breaking, but the pod itself is crisp enough to snap in the center when bent. The seeds inside should be small. Flavor declines rapidly when the pods and seeds are allowed to mature too much and your plants will stop producing pods. Try to avoid harvesting when the plants are wet because that is the optimal conditions for spreading any disease that may be present.
For fresh shelled beans, harvest the pods when the seeds are larger but still soft. The pods will be inedible at this point. For dried beans, allow the pods to dry on the plant. Once the plant is about dead and the beans rattle in the pods, harvest them. Shell the beans and separate the dried beans from the chaff.
To make sure your beans are dried enough for long-term storage, place several of them in a lidded jar for 24 hours. If there is condensation in the jar, your beans need more drying time. Once your beans have reached the appropriate level of dryness, keep them in an airtight jar in a cool, dry place.
There are several pests and diseases that can affect your bean plants. Mexican bean beetles, bean leaf beetles, and spider mites can all affect your plants. If your leaves are chewed up and skeletonized, Mexican bean beetles are the culprit. For smaller gardens, you can hand pick the beetles and larvae off the plants. For larger gardens, the use of predatory insects like wasps or spined soldier bugs can be released. Plant cilantro in amongst your beans to attract beneficial insects to your garden. You can also spray Neem oil on the underside of the plants every 7 to 10 days. Once you’re through harvesting, pull up the plants and destroy them. Do not put them in your compost pile.
Holes in the leaves and pods can be from bean leaf beetles and larvae. Plant crops early to avoid the period of heavy infestation and cover later plants with row covers. In the future, release beneficial nematodes at planting time to control these insects.
Pale speckles on the leaves are from spider mites and usually occur in dry, hot conditions. Spray the plants with insecticidal soap.
If the leaves on your beans turn yellow and die from the bottom up, this is probably the fungus Fusarium rot. Rotate beans off this patch of garden the next year, and kill the fungus by solarizing the dirt by covering with a clear plastic tarp in the heat of the summer for about six weeks.
Brown and black blotches on the pods are probably bacterial blight. You’ll need to pull up affected plants and destroy them. Do not add these diseased plants to your compost pile. In the future, apply a neutral copper fungicide spray when the plants are about 5 inches tall to help prevent the disease.
Look for aphids or root-knot nematodes if you have stunted plants with yellow leaves. Spray with insecticidal soap if aphids are present. If aphids are not visible, check for galls on the roots of the affected plants, which is a sign of nematodes. If root-rot nematodes are suspected, pull up the affected plants and destroy them. Practice crop rotation to avoid future occurrences and drench the soil with beneficial nematodes.