We add zucchini to almost everything we eat: soups, salads, stir-fries, smoothies, among others. If you eat as much zucchini as we do, then you know how important it is to grow them in the garden and get a good harvest. However, sometimes the perfect harvest is ruined by yellow leaves and diseased plants. Zucchini are very susceptible to many problems that can cause yellowing of the leaves. If this is not taken into account, a single yellow leaf can lead to loss of crop and eventual death of the plant. It is important to identify the cause of the yellowing leaves.
Why does the zucchini plant turn yellow?
Like all plants, zucchini produces chlorophyll. It is the pigment that turns a plant green and enables photosynthesis. Chlorosis is when the leaves of the plant turn yellow due to the loss of chlorophyll. Chlorotic leaves can be a major problem for a plant, being unsightly and easily burned by the summer sun. When a plant's leaves turn yellow, it is usually a sign that there is a more serious issue.Here are some problems, which occur in the garden and cause your zucchini leaves to turn yellow.
- Nutrient deficiencies and pH
- Overwatering and underwatering
- Pests as a possible cause
- Zucchini has been infected with a fungal or viral disease
- Zucchini doesn't get enough sunlight
Zucchini gets yellow leaves: nutrient deficiencies and pH
Iron is a key element for chlorophyll production. A zucchini plant only needs a small amount of iron to produce healthy, green leaves, but there are a number of reasons why your plant isn't getting enough of it. It's possible that the iron is trapped in your soil and cannot be absorbed by the roots. Also check the pH of your soil. Zucchini prefer a soil pH between 6.5 and 7.0. If the soil is more alkaline, this can lead to yellow leaves.
How to prevent nutrient deficiencies
The first step in addressing a nutrient imbalance is to have a soil sample tested. This way you will know exactly what you are dealing with and what you need to admit. As with most things in the garden, yellowing zucchini leaves can be remedied with compost or well-rotted manure (chicken or horse manure). These soil additives don't just delivervaluable plant food, but also help regulate nutrient imbalance. Compost also helps regulate pH if your soil is too alkaline.
Overwatering and underwatering
Another very common cause of yellow zucchini leaves is that the plants are receiving either too much or too little water. Zucchini attract nutrient-rich water through their roots. Additionally, most plants are 80 to 90% water, so they require adequate moisture to thrive.
Zucchini plants don't need as much water as you might think. About 2 cm to 3 cm of water per week is generally sufficient. If your zucchini doesn't get enough water, the plants begin to dry out and the wilted leaves often turn yellow. Because there is not enough water in the soil, the plant cannot absorb nutrients through the roots and chlorophyll cannot be produced in sufficient quantities.
What should you do about overwatering and underwatering?
When you water, be careful not to water the leaves as this can lead to fungal diseases. It is important that you know what type of soil you have and that you water especially carefully if you have heavy, clayey soil. For clay soils, the solution is to add compost, which loosens the soil and improves drainage. If the leaves turn yellow due to overwatering, it's best to wait until the soil dries out andthen wateragain, but this time in moderation.
If the zucchini leaves turn yellow due to drying out, you should water your bed. While it may be tempting to pour a lot of water on thirsty plants, doing so can lead to overwatering and create a whole new problem. Always water in moderation!
Zucchini leaves turn yellow because of pests
The zucchini plant issusceptible to pestssuch as aphids, spider mites and bedbugs. They can cause yellowing and wilting of the leaves as well as a mottled appearance to the plant. Once the leaves turn yellow and you recognize these pests, it's time to remove them from the garden to protect your zucchini.Annoying pestsThe best way to combat them is with beneficial insects. Mixed crops are also a good way to beautify your zucchini patch and attract beneficial predatory bugs. These predators are often also pollinators, so your zucchini benefit twice.
White spots mean illness
Gray mold, zucchini yellow mosaic virus, fusarium wilt andDowny mildeware among the main diseases responsible for yellow leaves of the zucchini plant. Remove diseased parts such as leaves and stems from the plant. Use organic neem oil or soap solution if the infection is widespread.
Yellow leaves on zucchini – insufficient sunlight
If there is not enough bright light, the leaves of the zucchini will begin to turn yellow. Zucchini need 4 – 5 hours of sun every day. If your plant is in the shade, move it to a location where it gets enough light.
Can you cut off yellow leaves from zucchini?
Pruning zucchini leaves is never a bad idea, but there are a few things to keep in mind. Feel free to remove a few yellow leaves, but at least let some leaves grow. Your zucchini should never be completely leafless.Cut themnear the stem, but be careful not to cut the stems themselves or the plant will become more susceptible to disease.
