Cucumbers can turn white when infected with powdery mildew, are overwatered or suffer from blanching. Any time a green variety cucumber turns white, it isn’t growing healthily.
There are white cucumber varieties available but you would have noticed when you bought the seed packet. Whenever any plant turns a color that is not its natural healthy state, there is something going on. That is definitely the case with cucumber leaves and fruit turning white.
Find out what causes white spots on cucumber skin and why cucumber plant leaves might turn yellow!
Why Is My Cucumber Plant Turning White?
It is important we make a distinction between the causes of cucumber fruit turning white and cucumber plant leaves becoming a paler color. In most cases, there is a different underlying reason and so must be addressed differently.
Let’s go through some of the potential causes behind both.
Why Are My Cucumber Leaves Turning White?
1. Powdery Mildew
Powdery mildew is the most common cause of cucumber plants, or any plant for that matter, turning white. It usually starts with cucumber leaves turning white around the edges and then its spreads to the entire leaf and other parts of the plant, including the fruit.
This fungal infection can occur at any stage in the growing phases. Both seedlings and more mature plants can be affected by it.
Mildew tends to form on plants when they are kept in high humidity with not enough air circulation. This can happen when you grow cucumbers too close together in a tropical environment or humid room.
2. Transplant Shock
Cucumbers plants are quite sensitive to a change in their environment. If you started cucumber seeds indoors and then transplanted them outside, you might notice the leaves turning paler.
This may be part of their initial shock and acclimatization process but it may also indicate other issues. If it is simply them adjusting to the weather outside, you have nothing to worry about.
Within a few days or weeks, the plant will have gotten used to the change in temperature and direct sunlight. If it doesn’t recover, it might be powdery mildew after all.
Why Are My Cucumber Fruits Turning White?
Very pale almost white cucumbers with yellowing leaves is what overwatered cucumbers look like. If you notice these two symptoms, leave the watering can where it is.
Cucumbers are 95% water so it is no surprise that they need a lot of water to grow. In certain climates, they even need daily watering.
However, this doesn’t apply to all growing conditions and people often make the mistake of overwatering their cucumber plants. If fruit themselves become lighter in color while the leaves turn limp and yellow, they have had more water than they need.
2. Root Disease
Plants absorb nutrients and moisture from the soil through their roots. So, if something is wrong with their roots, their health is affected, too.
Cucumber fruits turning white might be because the plant cannot absorb enough nutrients to facilitate healthy growth. This can be caused by root rot from overwatering or something may have been damaged when transplanting.
If there is a case of root disease, it is the fruit that will show the first signs. In the long run, the leaves will also start showing signs of issues with the roots.
What to Do with Cucumber Plants Turning White
Whether it is the cucumber leaves turning white or the fruit themselves, there is still a possible solution when you notice the change in time. That is why it is so important to check your cucumber plants daily.
This is what you can do if you notice white spots on cucumbers.
What Do You Do When Cucumber Leaves Turn White?
Since powdery mildew is the most common cause of cucumber leaves turning white, the best approach is to treat it as such. The fungus causing powdery mildew is quite difficult to get rid off but it is possible.
The easiest approach is to wash it away. All it takes is a mixture of mild organic soap and water, about 1 teaspoon of dish soap per 4 cups of water.
Spray this all over the cucumber plants, including the soil, and let it sit. You can also cut off the most affected parts of the plant.
Powdery mildew spreads very quickly to other plants so don’t postpone treatment. Whenever possible, isolate the affected plants from the others.
What Do You Do When Cucumber Fruit Turns White?
First, find out what is the cause; overwatering or a problem with the roots? The solution for each is different.
If you have recently transplanted the cucumber plant, a root problem may be the issue. However, if the soil is overly soggy and the leaves have turned yellow, overwatering is the more likely culprit.
There is no cure for root rot. The best thing you can is to remove the plant so that it doesn’t spread to the other plants.
The answer to overwatering is very simple; stop giving the cucumber plant water. Wait until the top 2 inches of soil have dried out before you resume an appropriate watering schedule.
Frequently Asked Questions:
Why Are My Cucumbers White and Yellow?
White cucumber fruit and yellow plant leaves are a sign of overwatering. Cucumber plants only need to be watered when the top inch of soil has dried out.
What Color Should Cucumbers Be When You Pick Them?
Cucumbers are ripe when they have a medium or dark green color but it is also important to check their firmness. Ripe cucumbers are firm so if they are a nice color green but still soft, they are not ready for picking yet.
Can You Eat Cucumbers with Powdery Mildew?
It is not safe to eat cucumbers with powdery mildew. Any signs of plant disease or rotting on a fruit or vegetable is a signal that it is no longer safe for consumption.
Notice white leaves on cucumber seedlings or cucumbers that are turning paler instead of greener? There is a good chance that something is going on with your cucumber plant.
White fuzz on cucumber plant is a sign of powdery mildew and this should be treated with soapy water asap. This fungus quickly spreads so act quickly.
Another possible cause is overwatering which is a much easier problem to address. Remember to only water cucumbers once the top inch of soil has dried out.
Root rot, is another possible cause of white cucumber plants but sadly there isn’t much that can be done about it. Still, it is better to remove the plant to avoid other roots nearby from becoming affected.
Find out what is happening to your cucumber plant and solve the problem.