Why Do Cucumbers Turn Yellow?

Cucumbers are great plants. They’re relatively easy to grow, but they’re also incredibly sensitive to their environment. One little mistake can ruin a whole crop if you don’t know how to deal with it quickly. 

There are most common issues that cause cucumbers to turn yellow—from underwatering or overfertilizing all the way up through genetic disorders and even pests like cucumber beetles.

Why Do Cucumbers Turn Yellow?


If you have been watering your cucumbers regularly and providing adequate water, but they are still turning yellow, then your soil may be lacking in nitrogen.

Cucumber plants need a steady supply of nitrogen for growth and production, so if there’s not enough available to the plant (i.e., in its soil), it will start to show signs by producing smaller fruit that grows slower than expected.

To increase the amount of nitrogen available to your plants, try adding some cottonseed meal into their soil every month or two during their growing season (April through October).

You can find these products at any garden center or hardware store. A small amount goes a long way.


When you have a cucumber plant and water them too much, the leaves will start to wilt and fall off. The same is true for overwatering—the leaves will begin to wilt if they’re provided with too much moisture.

If you notice any of these signs on your plants, try reducing your watering schedule by at least 25 percent until you see improvement in your garden’s health status; then continue adjusting accordingly as necessary so that all plants are getting enough but not too much water each day (and avoid using pesticides).


It’s possible that your cucumbers are turning yellow because you’ve overfertilized them.

This is a common mistake that can be easily avoided if you pay attention to the fertilizer instructions on the package.

When preparing the soil for planting, make sure to add only half of the recommended amount of fertilizer.

Wait until seedlings have reached about six inches high before adding more fertilizer and follow directions closely from then on.

Cucumber Beetles

Cucumber beetles are a common pest in cucumber fields. They can be controlled with pesticides, but you can also reduce the number of beetles by destroying the eggs before they hatch.

The larvae are the most destructive stage of their life cycle, as they chew through leaves and eat fruit that has not yet formed on your cukes.

Cucumber beetles can also cause your cucumbers to turn yellow by feeding on the plant itself, which results in damage that causes discoloration of the fruit itself.


Cucumbers can be a great addition to any diet, but they are not without their challenges. It’s important to know how to grow cucumbers so that you don’t waste your time and money on plants that won’t produce fruit.

If you’re concerned about whether or not the cucumber plant is getting enough sunlight or water, then take a look at our tips section for some helpful advice.