Yellowing green bean leaves are not always cause for concern—they can sometimes be a natural sign of aging in bean plants. But if you see leaves on green beans turning yellow mid-season, or if your plants are becoming less productive, it could be due to fungal, bacterial, or environmental stressors. Here are 6 common reasons why bean leaves turn yellow, plus simple, organic solutions to help your plants recover. Watering Stress Underwatering and overwatering can cause yellowing bean leaves, making it difficult to know exactly what’s going on with your plants. The best way to determine if your plants receive too much or too little water is to insert your finger into the soil. If the soil feels soggy and you haven’t watered recently, your plants are likely overwatered and root rot may be settling in. How to Fix Beans should receive about 1 inch of water per week. If you often forget to water, apply a layer of mulch around the base of your plants to keep the soil from drying out too quickly, and consider installing an automated drip irrigation system. If your plants are overwatered, adjust your watering schedule, scrape the mulch away from around your plant, and allow the soil to dry out before watering again. Lighting Issues Beans need at least 8 hours of direct light daily to grow. In low-light conditions, beans may develop yellowing leaves, but too much bright light can cause yellowing leaves, too. How to Fix Beans are difficult to transplant once established, but you can avoid lighting stress by choosing a growing spot that receives 8 to 10 hours of daily light. Nutrient Deficiencies Although beans fix nitrogen, they can still suffer from nutritional deficiencies in poor soil. Nutrient deficiencies produce different symptoms depending on what nutrients are missing; however, most deficiencies result in stunted plant growth and yellowing leaves with visible, green veins. How to Fix Testing your soil every few years and adding an annual application of compost is the best way to avoid plant nutrient deficiencies. You may also want to fertilize beans with an all-purpose fertilizer, adjust the pH of alkaline soils, and apply a legume inoculant to bean seeds before planting. Inoculants boost nitrogen fixation and make it easier for beans to absorb nutrients. Plant Diseases Diseases caused by bacteria, fungi, and viruses can produce yellowing bean leaves and other symptoms. Bacterial blight usually produces brown leaf spots with yellow halos. Bean mosaic virus may develop cupped or puckered leaves with a mottled yellow mosaic pattern. Fungal issues, like white mold and bean rust, may also produce leaf spots and yellow lesions, especially in overcrowded gardens. How to Fix Purchasing disease-resistant seeds from reliable seed companies can keep some plant diseases out of your garden. However, you can also reduce diseases by rotating crops, watering beans at the soil line, weeding regularly, following proper spacing guidelines, and destroying infested plant material at the end of the season. Pests While pests can cause yellowing leaves through the spread of plant diseases, sap-sucking pests may also directly cause yellowing leaves by feeding on plant sap. Pest damage typically presents as tiny dots or speckles on affected leaves, but pests may also skeletonize or chew holes in bean leaves. How to Fix Aphids, thrips, bean beetles, and spider mites are some of the most common bean pests, but these pests can be controlled with handpicking, organic soap sprays, and companion planting. Strongly scented herbs and flowers, like marigolds and nasturtiums, are especially good companion plants for natural pest control. Natural Processes While pests, diseases, and environmental stresses can cause bean leaves to yellow, aging bean plants may also develop yellowing leaves at the end of the growing season. Yellowing leaves caused by natural aging usually occur towards the base of the plant, and leaf yellowing may be exacerbated by cool temperatures. How to Fix Yellowing leaves that occur late in the growing season are a part of the natural aging process of bean plants and they signal that bean plants are reaching the end of their life. There is no need to address yellowing leaves caused by natural aging; however, you may be able to extend your bean growing season a little longer by installing season extension products, like row covers. 3 Additional Tips to Grow Great Green Beans If you want your bean plants to be even more productive, try out these quick and easy bean care tips! Trellising. Bush-type beans don’t need trellises, but pole and vining beans grow better with support. Cattle panel trellises are one of the best solutions if you want to grow lots of beans together, but you can also make DIY bean supports with bamboo poles or upcycled tomato cages. Spacing. To avoid fungal issues and other plant diseases, space bean plants at least 6 inches apart in rows that are at least 18 to 24 inches from each other. Harvesting. Regularly harvesting beans will make plants more productive, but don’t tug on bean pods when you harvest. Instead, pinch or cut bean pods off the plant so you don’t accidentally damage tender stems.




