Cucumber plant leaves gets its color due to a pigment known as chlorophyll. It is also responsible for photosynthesis process that converts sun energy into plant food.
Loss of this pigment results in chlorosis, yellowing of leaves.
Yellowing of cucumber leaves can be due to different causes, some can be easy fixed while other can be an indication of bigger problem.
Should I cut off yellow cucumber leaves?
Before trimming yellow leaves off the plant, you must first determine the cause of yellowing. Just removing the yellow foliage without rectifying the problem isn’t going to help.
If the lower old leaves are turning yellow, then you might worry, because it can be a natural process and the plant shed the leaves.
Overwatering, wrong potting soil, insufficient sunlight and pests can cause yellowing of cucumber leaves.
Let’s understand them in detail.
Check this out: How Much Sunlight Do Cucumbers Need?
Why your cucumber leaves are turning yellow?
As mentioned, chlorosis causes yellowing of leaves in plants. But what causes chlorosis?
1. Water problems – most common
Gardeners found overwatering or underwatering as common reason for yellowing of leaves.
Either you’re watering too much or too little. In both cases, plant leaves turn yellow.
Excess water results in oxygen deprived roots and rotting them. This problem could be due to choosing wrong growing medium that fail to drain excess water.
Similarly, not giving enough water can result in yellowing and wilting of leaves.
Also Read: How often to water cucumber plants?
2. Soil problems – wrong growing medium
Edible plants like cucumber are heavy feeders and they reap nutrients from soil. Low levels of nitrogen and potassium may result in yellowing of leaves.
Cucumber plant needs potting soil that is well drained and is rich in nutrients.
You must conduct soil test, if the result shows low levels of nitrogen, then adding fertilizers rich in nitrogen will help to fix yellowing of cucumber leaves.
3. Sunlight – plant not getting enough sunlight
Plant leaves that don’t get enough sunlight fail to produce food and thus turn yellow.
Shift the cucumber plant where it can get at-least 6-8 hours of sunlight.
Relocating climbers isn’t easy, but to save the plant you must carry on this hectic work.
In case, if your cucumber plant leaves are getting sunburned due to harsh sun, use shade cloth to protect your plant.
Pests like aphids, leafhoppers, whiteflies and spider mites are cause discoloration of cucumber leaves.
Gardening experts recommend using insecticide to protect your plant leaves and to have quality yield.
Also Read: What Not to Plant With Cucumbers?
Can you fix them?
Once you indentify the underlying cause of yellowing, you can easily fix.
If the problem is due to overwatering regulate watering schedule and in case of underwatering increase the watering frequency.
Choosing well-drained soil plays vital role in solving overwatering issue of your plant.
As mentioned to overcome insufficient sunlight issue, you can relocate the plant where it gets at-least 6-7 hours of direct sunlight.
Use potassium rich fertilizer and Epsom salt to overcome low levels of magnesium and sulphur.
Using insecticide will help to get rid of pests that cause yellowing of leaves.
Why Should I Cut Off Yellow Cucumber Leaves?
If the yellowing of leaves is due to pests or diseases, cutting them may reduce the spread to some extent, though not completely.
Removing old leaves that are at the bottom of the plant can actually help your plant. Instead of wasting the energy on yellow leaves, cucumber plant will use it to produce blossoms and fruits.
Naturally your cucumber plant leaves decommission old plants leaves that are at the bottom of the plant. You can remove these leaves or with natural course the leaves will shed by themselves.
However, trimming yellow leaves is not the solution in all cases.
- First step is to determine the cause of yellowing and try to fix the problem.
- After fixing the issue, allow the plant to recover from underwatering or overwatering issues.
- Apart from this, check with potting soil in the container. It should be well drained and rich in nutrients.
- Sufficient sunlight, water and free from pests, will help to get rid of yellow leaves.
Note: Soil pH, lack of nutrients in soil and water quality can result in discoloration of leaves.
Also Read: How Long Does it Take for Cucumber to Grow?
Can yellow leaves turn green again?
In most cases it is impossible to reverse the color of yellow leaves to green. However, in rare cases when you acted swiftly yellow spots on leaves can turn green.
If you regularly supply adequate amount of water, sunlight and fertilizers new leaves won’t turn yellow in early stages. You must remember that old leaves will turn yellow before dropping.
You must worry when new leaves turn yellow at early stages.
Also Read: How Often to Fertilize Cucumber Plants?
Can you remove yellow leaves?
A fully yellow turned leaf indicates that it isn’t producing enough energy for the plant. If you allow the nature to take its course, the yellow plant leaf will fall off.
For aesthetic appeal, you can gently remove bottom yellow leaves of the plant.
Note: Removing excess leaves can impact plant growth and yield.
Pruning Cucumber Leaves
Bush cucumbers don’t really need pruning most of the time. Little pruning can be done if they’re leaning towards neighboring plants.
Vine cucumber plants will benefit more from pruning. It is very important to make your vine grow in the right direction.
Prune shoots that come up from the main stem. Find 5-7 nodes at the base of the cucumber plant and pinch off using clippers.
Similarly, remove leaves and stems that are damaged and discolored.
When you trim yellow leaves and shoots at the bottom of the plant, the energy will be redirected elsewhere. Pruning or cutting off damaged leaves and shoots will eventually help in increase the quality of fruit. (Source)
How to Grow Cucumber Plant and Avoid Yellow Leaves?
Take cucumber seeds to germinate in coco peat or in tissue paper.
Sow cucumber seedlings in a container filled with well drained potting soil. As the cucumber plant has shallow roots, leave 10 cm on the top of container so that when roots starts to develop you can cover them using more fertile soil.
Cucumber plant needs 8 hours of direct sunlight. Place the plant in a location that gets enough sunlight.
Watering at right time is very essential for avoiding plant problems like yellow leaves.
Insert your finger and check the soil for dryness. If the soil isn’t sticky, then you must water generously till you see the water is drained out of the hole.
Watering frequency can be regulated according to climatic conditions in your region.
Important: Conduct soil test to know NPK ratio. Low levels of nitrogen and potassium can result in poor discolored leaves.
Get rid of aphids and other pests that again damage cucumber plant leaves.
Use trellis to allow the vine to grow and you can easily harvest the fruit.
Also Read: How Deep Do Cucumber Roots Grow?
Can you remove yellow leaves on cucumber plant?
Yes, but not before knowing the root cause of yellowing.
If the plant leaves are turning yellow as a natural aging process, then you don’t have to worry. Just cut it off.
If the chlorosis is due to overwatering, underwatering, wrong soil, insufficient sunlight or pests, then you must fix this problem at the earliest. Else, your whole plant will die.
Just trimming the yellow leaves without solving its cause will not help the plant.
Watering problem is one of the most common issues many new gardeners face. Yellowing of leaves is a sign that your plant is having issue.
Check the surface of potting soil, if it bone dry and leaves are dropping then probably the plant isn’t getting enough water.
If the surface of soil has algae and getting rotting smell, then you’re overwatering your plant. In other words, the growing medium isn’t well drained.
Once you fix the problem, allow the plant to recover.
Yes, you can now cut or remove leaves that turned fully yellow.