When cucumbers turn yellow leaves: the possible causes and what you can do

Are your cucumbers not growing and turning yellow leaves? A sure sign that the plant is stressed. Diseases, pests or incorrect care could cause leaf drop. We list the most common causes.

Cucumbers get yellow leaves: diseases, pests or care mistakes?

When the cucumber leaves turn yellow, as a hobby gardener you ask yourself what could be the cause. Diseases, pests and one or two care errors are among the most common causes of yellowing. It is very important to take a close look at the plant and answer the following questions:

  • Are the leaves sticky?
  • Are spider webs visible on the leaves and shoots?
  • Has the cucumber stopped growing?
  • Does the plant droop its leaves?
  • Is the soil dry or too moist?
  • Is the humidity in the greenhouse too low? The large cucumber leaves evaporate a lot of water and therefore require high humidity.
  • Is it too cold in the greenhouse? Temperatures should not fall below 18 degrees Celsius.

These questions are crucialso that the cause can be identifiedand can save the plants.

Aphids on cucumbers: common cause of yellow leaves

Aphids often attack cucumber plants grown outdoors. The pests can rarely be found in greenhouses - and especially when the humidity is too low.

An infestation becomes noticeable quickly. The plants first droop their leaves, then turn yellow and the leaves then fall off. A sure sign of aphids is the sticky coating on the top of the leaves.

An aphid infestation is favored by low humidity and temperatures around 20 degrees. By the way, aphids also transmit a disease - cucumber mosaic virus, which can lead to leaf discoloration. Yellow, mosaic-like spots appear on the leaves and fruits, which then become inedible.

What you can do: Cover the outdoor plants with translucent fleece. The lice do not like high humidity and will relocate. You can also oneMake your own sprays. Plant disease-resistant cucumber varieties as prevention against cucumber mosaic virus.