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Why Are My Squash Plant Leaves Turning Brown – Causes & Fixes

Like any crop, squash can be particular in its growing needs and may show weird symptoms that must be corrected. For example, squash plants can manifest issues with their leaves, such as color changing. If you’ve stumbled across this article, you are probably wondering, why are my squash plant leaves turning brown?

Squash plant leaves can turn brown when they are receiving an inadequate amount of water. Other reasons include nutrient imbalance, or outdoor temperatures that are too cold for them to thrive. Lastly, with any plant, you risk them getting exposure to pests, fungus, or disease. Your squash may have been taken over or infected by an environmental threat. 

Don’t you worry. Continue reading to learn more about why your squash plant leaves turn brown and how to prevent and cure the issue.

Specific Reasons For Brown Squash Leaves/Prevention Techniques

Inadequate Watering-

Overwatering your squash plants can be an issue. An abundance of water that is not needed will drown out the roots of your plants and can cause them to rot. This can cause your squash plant leaves to brown. Underwatering can also be a problem. A lack of water will cause your plants to dry, turning the leaves brown. 

Prevention: 

Stick your finger one inch below the surface of the soil. If it’s moist, your squash plants most likely don’t need to be watered. If the soils are very dry, give your squash plants a good watering session. Instead of watering a little bit daily, water your squash heavily, once or twice a week. That way, there’s time for the water to work itself down into the roots and nourish the entire plant. 

Nutrient Deficiencies-

Squash plants need proper nutrients to keep their color and liveliness. They specifically need Phosphorus, nitrogen, and potassium. A lack of either of those nutrients can cause your squash plant leaves to alter in color and possibly wilt or die.

Prevention: 

If you don’t already have fertilizer with phosphorus, nitrogen, and potassium, run to your local home and garden store to purchase some. Fertilize multiple times throughout the season. Also, ensure you use well-fertilized soil to plant your squash plants. Don’t use old, lacking soil. You can’t rely on only fertilizing after your squash seeds or starts have already been planted. 

Cold Temperatures-

Like many fruit and vegetable crops, squash does not thrive in cold weather. Outdoor temperatures must remain above 50 degrees Fahrenheit, and root temperatures must be above 62 degrees Fahrenheit to ensure that squash leaves will not turn brown or die.

Prevention:

To be safe, you must wait 6-8 weeks after the last frost date has passed to plant your squash seeds or starts. This will guarantee that the outdoor weather conditions will be suitable for growing your squash plants and keeping the leaves healthy and colorful.

Pests-

Bugs love to feed off of squash plants. They will specifically feed off the leaves, making them weaker and leaving residue that damages them. As squash bugs slowly kill the leaves, they will turn brown. Other insects that could be attacking your squash plants are aphids and vine borers. 

Prevention:

Gently lift your squash plant leaves and identify insects, clusters, or eggs. Remove them from the bottom of the leaves with gloves and place them in a soap and water mixture to kill them and ensure they won’t come back. You can also spray them with water to remove them. No guarantee they will die and won’t return or attack another plant in your garden. 

Fungal Diseases-

Downy Mildew, powdery mildew, and angular leaf spot are all fungal diseases that can cause squash plant leaves to dry out, kill leaf structure, and turn brown. Fungal disease can be caused by too much moisture. Also, bugs eat away at leaves, making them weak and more susceptible to a fungal disease. 

Prevention:

First, try watering your squash plants early in the day to ensure they have adequate time to dry in the sun. Also, follow the abovementioned process of removing bugs to keep your squash plant leaves strong and less prone to disease. Lastly, If you are watering and nourishing your plant adequately and the leaves are still turning brown, then chances are, if there are no bugs, your plant has a disease. Spray the leaves with an organic fungicide that won’t damage your plants but will kill off any fungal disease. 

Should I Remove Brown Or Dead Squash Leaves?

Do not remove brown or dead squash leaves from your plant. In doing so, you cut the plant open and expose it to pests and disease. Also, squash plant leaves act as protectors from the sun, so the squashes themselves don’t receive sunscald. Trust that your squash plants will let go of brown or dead leaves when they are no longer needed. Trying to remove them may only cause more damage. 

Final Thoughts

Every crop has a chance of not surviving, and that can be a sad thought. Browning leaves are typically a good indicator that something isn’t right. Use this article as a checklist to understand why your squash plant leaves are turning brown. First, ensure your squash plants are well nourished.

This includes water, sunlight, and the essential three nutrients of potassium, phosphorus, and nitrogen. If you are watering and nourishing correctly, your squash plants are being attacked or infected by a pest or disease.

Prevention techniques are listed in the article above. Use this article to practice the process of elimination technique, and you will indeed discover why your squash leaves are turning brown. Don’t worry; there will surely be a cure wherever there’s a problem.