If your yellowing cucumber leaves plant leaves are yellowing, it could be due to chlorosis, a condition in which the green pigment that gives plants their distinctive color is reduced. Chlorophyll is essential for a plant to gather sunlight and convert it into energy, so any loss of this substance means that your cucumber plants are not getting enough nutrients. There are several causes of chlorosis, so the first step in rectifying it is determining what’s wrong with your cucumber plant.

Cucumber plants are heavy feeders, so they require a wide range of nutrients to grow and stay healthy. A soil test is a good way to find out what is missing from your garden or greenhouse soil and then amend it with a fertilizer formulated for your needs. Typically, cucumber plants need 1 to 2 inches of water a week in well-draining soil. Using drip irrigation can make sure that the soil stays moist and avoid overwatering, which also leads to a number of problems.

Yellowing Cucumber Leaves: Causes and Cures for a Thriving Crop

Pests that suck the sap from the leaves of cucumber plants can cause them to turn yellow. Common culprits include aphids, potato leafhoppers, spider mites and whiteflies. These pests can be spotted by looking at the underside of cucumber plant leaves where they will leave a fine silver webbing.

A lack of nitrogen can also cause cucumber leaves to turn yellow, and this is easily fixed by adding a fertilizer with a high nitrogen content. Add one tablespoon of ammonium nitrate when the flowers begin to bloom and then again three weeks later.