Cucumber Leaves Turn Yellow: The Reasons and How to Prevent This

Do you have a vegetable garden and are also fond of having your own home-grown vegetables? If so, then you might want to know that gardening comes with its share of challenges. One such challenge is discolored leaves – or yellowing. Discolored leaves can occur when the pH level of the soil is high, making it less acidic than the leaves themselves.

This results in the plant’s pigment molecules breaking down faster than they can be replaced, which ultimately gives the leaves that yellow appearance. There could be many reasons for yellowing cucumber leaves; some more serious than others: The following article explores each one and gives helpful tips to help prevent it from happening again.

Why Cucumber Leaves Turn Yellow?

Many vegetables, herbs, and fruits are grown in soil that is higher in pH than the leaves themselves. This means that the leaves have a certain amount of alkalinity in their composition.

Some vegetables, however, are grown in soil that is too low in pH. When this happens, the alkalinity in the leaves gets diluted, which makes them vulnerable to various conditions.

The root system of your cucumbers could be one of the reasons yellow leaves are appearing. The excessive alkalinity in the soil is one of the reasons why the leaves become yellow.

You could solve this by adding more organic matter and/or soil amendments such as limestone or sulfur. You could also try planting your cucumbers in containers so they are not subjected to the soil.

What You Can Do to Prevent Yellowing

Pick Young Cucumbers: No, we are not talking about the picky eater you have who refused to take any cucumbers off the vine. We are talking about the still-green cucumbers that you could be eating right now. Young cucumbers tend to have bright green leaves and fewer seeds.

When the leaves turn yellow, it is often because the leaves of the cucumber are yellowing. Not only is it unattractive, but it is also part of the aging process. When cucumbers are eaten before they are fully ripe, they have a milder flavour and are less liable to cause an upset stomach.

You could try leaving them on the vine until they turn yellow and then picking them. Young cucumbers tend to be more watery and less seed-y than fully-ripe cucumbers.

Add Mulch: Mulch is used to keep the soil cool, which in turn reduces the amount of water (and electricity) used by vegetables during the heating season. It is especially important to add mulch to your garden during the summer.

Pick Fungal Infected Leaves: When leaves start to yellow, it is a sign that fungi are present in the soil. You should dig out the affected soil and replace it with fresh organic matter.

Change the pH of the Soil: If your soil is too alkaline, the leaves of your vegetables are likely to discolor. You can correct this by adding organic matter, such as compost or well-aged manure.

Add pH-Balancing Salt: There are vegetables that prefer a more acidic soil (such as tomatoes, potatoes, and eggplants). If your soil is too alkaline, you can add a small amount of a pH-balancing salt like gypsum to the soil.

How to Stop Cucumber Leaves from Yellowing?

To stop cucumber leaves from yellowing, make sure the cucumbers are fully ripe before harvesting. You could pick them green and then leave them on the vine for a few more days until they are fully ripe.

Alternatively, you could buy cucumber plants that are specifically bred for outdoor cultivation. Avoid adding too much nitrogen to your soil as this encourages the growth of leafy vegetables, but not fruit-producing vegetables.

You could try growing your vegetables in containers so they are not subjected to the soil. When harvesting your cucumbers, do not peel them. Peeling the cucumbers results in the loss of much of the cucumber’s nutrients and is one of the reasons why cucumber leaves are discolored.


While many vegetables will yellow with age, cucumbers are more prone to this problem than others. It is caused by the increased alkalinity of the soil, which in turn causes the pigment in the leaves to be broken down more quickly.

Cucumbers are also more likely to be grown in soil that is too alkaline than other vegetables. There are many ways to prevent yellowing of cucumber leaves, but the best way is to grow cucumbers in a well-watered, well-aerated soil.

A well-drained soil with good organic matter and a pH of around 6.5 is ideal. Cucumber leaves yellowing is not a serious problem and can be prevented. These tips will help you prevent yellowing of cucumber leaves.