Why are My Cucumbers Leaves Turning Yellow & Dying?

Unless you’re a superhuman who happens to garden as well, you’re more than likely to wake up one morning and realize that some of your vegetable leaves have turned yellow. If your cucumbers leaves turning yellow you might have a problem.

Don’t panic – this happens to the best of us! Next, you might be wondering why it happened. I am here to clear that issue up and help you correct it.

Having had my fair share of failed vegetable gardening I consider myself somewhat a pro when it comes to fixing these types of problems.

Why Do Cucumber Leaves Turn Yellow?

While the most common reason for cucumber leaves turning yellow will be because of a watering problem, other factors like light, pests, disease or a potassium, iron or nitrogen deficiency can also cause your leaves to turn yellow.

Thankfully, Once you’re able to determine what is causing your cucumber leaves to turn yellow, you can figure out what to do about it.

We will take a look at the four major factors in causing Cucumber leaves to turn yellow:

1. Water Levels

This is probably the easiest problem to solve. Just water less or more. If you get stuck at this step, read through guides like these to help you determine how much water your plants need.

You can also make use of to handy gadgets help you measure the moisture in your soil and prevent you from over – or under-watering your plants.

Getting this step wrong can cause leaves to turn yellow without any other harmful factors being present.

2. Light

Cucumber plants love sunlight! If your plants aren’t in the sun long enough, no amount of water or nutrients will help it grow.

Cucumbers need at least 6 hours of sun per day, but some might enjoy 8 hours better. Whether you’re growing your cucumbers under artificial light of making use of the good old sun, you need to make sure that they are getting enough of it.

3. Pests and Disease

If you’re dealing with pests you need to determine which they are. Common pests that love to feed on cucumber plants and leaves are potato leafhoppers, aphids, spider, mites or whiteflies.

These pests can all be treated by using prepared insecticidal soaps or removing leaves from the bottom of your plants. Other methods are also available and reading up on them is always a good idea!

Treating diseases on your cucumber plants is a whole other story. The Mosiac virus and verticillium wilt are spread by pests or found in the soil as a result of previous crops.

Unfortunately, there is no way to treat these two common diseases. To my shock, I found that you need to remove your infested plants as soon as possible to prevent the diseases from spreading.

You will also have to be wary of planting in that soil the next season since these diseases can keep infecting for up to a year!

Some other diseases are easier to treat. If you notice white powdery spots and coating on your cucumber leaves, it is only a fungal spore and picking off the infected leaves as well as not overwatering will clear up this problem.

Yellow and brown spots indicate downy mildew. Improving air circulation and keeping your garden free of debris will solve this problem.

4. Deficiencies

Deficiencies can each be treated in their own way. That’s why you’ll need to determine which deficiency is making your plant leaves turn yellow. I decided to break each common deficiency down for you.

Nitrogen deficiency can be cured by buying soil fertilizer that uses the proper dilution rate. Even a slight mishap here will damage your cucumber plants. Using organic fertilizers work best in my experience.

Potassium deficiencies are caused by excess calcium, sodium or nitrogen, so you need to feed your plants with organic nutrients that are right for the growth stage in which the plants find themselves. During the flowering stage, this potassium need tends to be higher.

For iron deficiencies, you can either treat the plant or treat the soil – doing both is a bonus, but remember that balance is key.

Liquid iron can be sprayed on plant foliage, although this isn’t a lasting solution. To treat soil, you can use either powdered or granular chelated iron that you’ll have to sprinkle around the root zone.

Growing a vegetable garden and being able to harvest your crops is a very rewarding feeling! I am big on gardening and nothing gets me under as fast as dead plants.

Educating yourself on what causes this and how to fix it is the best thing you can do for yourself and your garden.

Whether you garden as they did in the old days or make use of modern gadgets to help you along, a harvest-ready crop equals a happy gardener and in the end that is all that matters. These are the reasons why cucumbers leaves turning yellow.

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