How Bean Plants Need Light & Water


Beans are perhaps one of the most popular home garden crops. Beans of all varieties are best grown in sunny locations and well-mulched soils with good drainage. Once beans begin to produce their edible pods, they will continue to produce for several weeks, making a healthy and delicious addition to summer meals.


Beans are warm weather crops. Plant in the spring after all danger of frost has passed and the soil temperature has warmed (preferably to at least 50 degrees). Beans prefer full sun. Choose a location in your garden that receives sunlight for most of the day.

Importance of Light

Beans, like all other plants, use light to turn carbon dioxide from the air and water into food. This process is known as photosynthesis. Light is taken in through plant leaves and turned into a simple sugar. Beans need light in order to bloom and produce fruit. With too little light, beans may not flower, or, if they have flowered, those blossoms may drop prematurely.

Extreme Temperatures

Associated with the importance of appropriate light exposure is the importance of protecting bean plants from extreme heat and cold fluctuations. Extreme temperatures or humididty can cause plants to drop their blooms. If you live in a temperate climate such as the Pacific Northwest, you may not have to worry about extreme temperature changes. In hotter climates such as the Southwest or Southeast, however, you may need to take precautions to protect your plants during excessive heat waves or abnormal cooling. Shade clothes can be placed over plants during high temperatures to minimize damage.

Importance of Water

Beans use water to create their food. During hot summer months plants will need more water in order to continue to produce blooms, pods and fruit. Monitor your soil's moisture level during periods of hot temperatures. You may have to water more often. Most water is absorbed by the roots and then carried to the rest of the plant through a process called capillary action. Water also carries other important nutrients from the soil to the rest of the plant. These nutrients are important to healthy bloom and fruit production.

How to Water

Minimize plant stress by watering your beans approximately one inch a week. During germination, keep soil moist at all times. Be careful not to over saturate the soil, which can result in seed rot. Maintaining appropriate soil moisture as plants mature is important to pod development. Over watering can result in premature flowering and pod dropping. If you use an overhead watering method such as a sprinkler, water in the mornings so plant leaves have an opportunity to dry during the day, minimizing the chances of disease in your plants.

Keywords: growing beans, watering beans, bean propogation

About this Author

Erika Sanders has been writing since 1997. She teaches writing at the Washington State Reformatory and edits the monthly newsletter for the Collaborative on Health and the Environment, a national nonprofit organization. She received her Master of Fine Arts in fiction from the Solstice MFA Program at Pine Manor College in Boston.