The common bean plant (Phaseolus vulgaris) includes an enormous number of varieties of pod/snap beans that have edible pods, but also shell beans and dry beans, in which the inner seeds are removed from inedible pods before they are prepared and eaten. Most home gardeners will be raising the pod/snap type, which includes both pole bean varieties that grow long vines as well as low-growing bush beans. Most varieties of pod/snap beans are green, but there are also purple, red, yellow, and streaked beans. Common beans are several inches long and either round or flattened in shape.
Bean plants are annual vegetables that grow quickly and are best planted in the spring. The flowers appear about two months after planting. Harvest time varies greatly, depending on the type of bean. Note that the seeds of raw or undercooked beans can be toxic to people and animals.
|Common Name||Common bean, green bean, French bean, snap bean, string bean|
|Botanical Name||Phaseolus vulgaris|
|Plant Type||Annual, vegetable|
|Size||2–15 ft. tall, 2–3 ft. wide|
|Sun Exposure||Full sun|
|Soil Type||Loamy, moist, well-drained|
|Hardiness Zones||2–11 (USDA)|
|Native Area||South America, Central America|
|Toxicity||Toxic to people, toxic to pets|
How to Plant Common Beans
When to Plant
The most important rule of growing common beans is not to plant too early. Plant in the spring after all danger of frost has passed. Seeds sown too early can rot in cold, damp soil, and the plants need warm weather to thrive.
Selecting a Planting Site
Choose a planting site that gets lots of sun and has organically rich soil with sharp drainage. Make sure there are no tall shrubs or trees nearby that will create too much shade for the beans. Beans also can be grown in raised beds and containers.
Spacing, Depth, and Support
In general, plant seeds about an inch deep, and position nursery plants at the same depth they were in their previous container.
- Bush beans can be planted in rows 2.5 to 3 feet apart, with seeds placed 1 to 2 inches apart. After the plants germinate, thin the seedlings to 3 to 4 inches apart.
- Pole beans need some type of support on which to grow. The support should be 6 to 8 feet tall. Be sure the support is in place before you seed. Space supports roughly 3 to 4 feet apart.
Common Bean Care
Beans need full sun for the best yield. Full sun also helps to keep the plants dry and less likely to be affected by certain issues, such as fungal diseases.
Beans like organically rich loamy soil with a slightly acidic pH. Good soil drainage also is key. Remove weeds prior to planting to prevent competition for soil nutrients and moisture. As the beans grow, weed carefully around the plants, as their shallow roots can be easily damaged.
Common beans need 1 inch of water per week. Use a drip irrigation system for supplemental watering to avoid splashing soil onto the leaves, which can lead to soil-borne diseases. To determine whether the plants need water, stick your finger about 1 inch into the soil near the base of the plant. If the soil is dry, it's time to water. Plants that are underwatered will stop flowering. Beans have shallow roots, and mulching can help to keep them cool and preserve moisture in the soil.
Temperature and Humidity
Common beans germinate best when the soil temperature is between 70 and 80 degrees. If the soil temperature is below 60 degrees, seeds will germinate more slowly and are susceptible to rot. The plants grow best when the air temperature is between 65 and 85 degrees. Beans tend to stop flowering in the extreme heat of summer. But keep them well-watered, and they will resume flowering and production when temperatures cool. Moreover, common beans grow in all humidity conditions if properly watered.
As legumes, beans fix nitrogen in the soil, so avoid a high-nitrogen fertilizer. Instead, use a 10-20-10 fertilizer to feed the plants throughout the growing season, following the product directions. Pole beans produce over such a long period that they also will benefit from a side dressing of compost about halfway through their growing season.
Most bean varieties are self-pollinators. The blossoms are so-called "perfect flowers" that include both male and female parts. Pollination within each flower usually happens reliably just from gentle breezes, though bees and other pollinators can assist in the process. But it is not necessary to grow different varieties or multiple plants in order to ensure cross-pollination, as is the case with some species.
Types of Common Beans
In the most popular pod/snap category, there are several types of common beans, including:
- 'Kentucky Wonder': This old pole variety of string bean is prized for its flavor.
- 'Bountiful': This is an early-producing, stringless heirloom bush bean.
- 'Golden Wax Bean': This is a soft-textured, yellow bush bean.
- 'Royal Burgundy': An early-producing bush bean, it has purple pods that turn green when cooked.
- 'Romano': This classic broad, Italian-style, bush or pole bean has a meaty flavor.
Pod/Snap Beans vs. Shell Beans vs. Dry Beans
The various varieties of Phaseolus vulgaris are categorized into three types:
- Pod/snap beans: These are the most popular beans for most gardeners, comprising both low-growing bush beans and tall pole beans in which the entire pods are prepared and consumed whole—outer pod as well as inner seeds. This group represents what most people think of as green beans. Bush varieties typically grow 18 to 30 inches tall and are self-supporting, while pole varieties have vines that can climb or sprawl as much as 15 feet.
- Shell beans: With this type, the pod is not eaten, but rather the beans are removed from the pod as they approach maturity. The beans are prepared and eaten while still soft.
- Dry beans: Including kidney beans, white beans, yellow beans, navy beans, and pinto beans, the varieties in this group are generally shelled and stored dry or canned for later use.
It's important to distinguish between these types, as it will dictate how you prepare and eat them. Make sure to buy a variety that fits your expectations.
Harvesting Common Beans
Harvesting beans is an ongoing task, and the more you pick, the more beans the plants will set. You can start to harvest anytime after the beans form. Gardeners usually harvest the beans when the pods are young and tender, about the size of a small pencil. The inner seeds should not yet be visible through the pods. Overly mature beans, where the inner seeds can be seen bulging through the walls of the pod, can be tough and stringy.
In general, bush beans are ready to pick in 50 to 55 days after planting. Pole beans will take 55 to 65 days, depending on the variety. Check the packet to be sure your choice will have time to mature in your growing season. Harvest by gently pulling each bean from the vine or by snapping them off at the vine end. Be careful not to damage the plant when harvesting. You can cook the beans right away or blanch and freeze them. They can keep in the freezer for up to a year.
How to Grow Common Beans in Pots
Growing beans in a container can be helpful, especially when it comes time to regularly harvest your crop. As long as the container gets enough sunlight, you can place it in a spot that’s convenient for you to visit regularly.
Choose one of the smaller bean varieties if you wish to grow them in containers, and be sure to give pole beans a support structure on which to grow. Aim for a container that is at least 1 foot deep with ample drainage holes. An unglazed clay container is ideal because it will allow excess soil moisture to evaporate through its walls. Wood barrels also can make good planters.
No pruning is necessary for common beans, other than pulling the plants from the ground as cold weather sets in. These are annual plants that do not return the following spring. Allow the beans to continue to grow as long as possible, as these legumes actually improve the soil by absorbing nitrogen from the air and fixing it in the soil. Some gardeners like to rotate the planting location of legume species like beans and peas around the garden to take advantage of this soil-improving property.
Propagating Common Beans
Bean plants are propagated via seed. Because the plants are annuals, this is an inexpensive way to ensure you have new plants each year. Here’s how to save the seeds:
- Harvest seed pods from a healthy bean plant once the pods have dried and become brittle.
- Break open the pods to release the seeds.
- Store the seeds in a dark, dry, cool spot within an airtight container. They should be viable for three to four years and can be planted in the spring after the threat of frost has passed.
Be aware, however, that only non-hybrid, open-pollinated plants will produce seeds that grow into plants identical to the parents. If you try this with hybrid varieties, you are likely to be disappointed with plants that do not have the same characteristics as the parent plant.
How to Grow Common Beans From Seed
Bean seeds are generally direct sown in the garden, as they dislike being transplanted. Their roots are shallow and easily damaged. If you want to start beans inside, plant them in biodegradable pots or soil blocks that can be planted into the garden once the weather has warmed.
Potting and Repotting Common Beans
A quality potting mix that’s labeled for vegetables is usually ideal for growing beans. As long as you plant in a large enough container, you won’t have to repot these annuals during the growing season and disturb their roots.
Common Pests and Plant Diseases
Several animal pests love bean plants, including:
- Mexican bean beetles will eat the flowers, the beans, and especially the leaves.
- Spider mites pierce the leaf surface and suck the sap, often causing leaves to die.
- Japanese beetles and aphids may also attack bean plants.
- Bean leaf beetles can girdle the stems near the soil line and chew holes in the plant's leaves.
- Deer and groundhogs will eat entire bean plants, and fencing is necessary to stop them if they are prevalent in your area.
Fungal diseases, such as Alternaria leaf spot, can be a problem in damp conditions. Other diseases, including white mold, bean rust, and mosaic virus, can also affect bean plants. Help prevent diseases by keeping the vines dry. Also, don't overcrowd the plants, and provide plenty of air circulation. You can look for plant varieties that are bred for disease resistance.
Are common beans easy to grow?
Beans are easy to grow if you can meet their light and moisture needs.
How long does it take to grow common beans?
Beans are generally ready for harvesting in around two months after planting.
Can you grow common beans indoors?
Beans can be grown indoors but will likely need grow lights to supplement natural sunlight.
Phaseolus Vulgaris (Bean, Beans, Green Bean, Green Beans). North Carolina State Extension.
Plants Poisonous to Livestock. Cornell University Department of Animal Science
Phaseolus vulgaris. Missouri Botanical Garden.