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How To Keep Cucumber Plants Healthy! Avoiding Powdery Mildew

Nothing can destroy an otherwise healthy crop of cucumber plants like a battle with powdery mildew disease.

Cucumbers are one of the most popular vegetables grown in home gardens. Prized not only for fresh eating, they also are the star of the show when it comes to making delicious pickles.

But growing them can be a bit tricky at times.

Especially when it comes to protecting them from the deadly disease of powdery mildew.

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Powdery mildew begins with a few white or grayish-white spots appearing on the foliage of plants.

Although it can attack many vegetables, it is especially devastating to cucumber, melon, pumpkin and zucchini plants.

The spots are actually a fungus that will continue to form on the leaves, eventually leading to the complete collapse of the plant.

The key to keeping plants safe from this disease all lies with prevention.

Unfortunately, once the tell-tale white spots appear on the leaves, it is often too late to help the plant.

But with the few key preventive measures noted below, you can most often keep this deadly scourge at bay. And in the process, enjoy a banner crop of cucumbers!

How To Protect Cucumber Plants From Powdery Mildew

Mildew forms best in cool, wet conditions.

The longer plants are around excess moisture and lower temperatures, the more likely it is that they can develop the ailment.

Plant In A Sunny Location

For starters, always plant your cucumbers in a location that receives at least 8 hours of full sun.

dew on plants
If morning dew is unable to dry off, it sets the stage for mildew.

The sun provides more than just the warmth plants need. It also allows leaves and vines to dry off from early morning dew.

The faster vines and foliage dry in the early cool morning, the less likely it is for mildew to start.

Avoid Watering At Night – Preventing Powdery Mildew

As with many vegetable plants, watering cucumbers at night can increase the risk of issues.

Watering at night keeps heavy moisture around the stems and leaves at the worst time possible – when temperatures are cooler.

Watering plants early in the morning is the best time of all. This allows the plants to quickly dry off as the sun rises, and day time temperature heat up.

powdery mildew
Watering at night can provide the perfect conditions for mildew to flourish.

And when you do water, keep from spraying the entire plant with a stream of water.

Instead, water right at or near the root zones of the plants. This keeps the foliage from becoming overly saturated for extended periods.

Providing A Mulch Or Soil Cover For Plants

Mulching or covering the soil below your plants is an excellent way to help prevent a whole slew of issues for cucumber plants – including mildew.

Mulch helps to keep the soil temperatures regulated from the high heat of the day, and the low temps at night.

mulching plants to avoid powdery mildew
Landscape fabric allow water to get to roots, and keeps plants from directly touching the soil.

It also keeps the foliage and vines of plants from directly touching the soil, which can make it hard for plants to dry out, and make them more susceptible to soil borne diseases.

Using a landscape cloth or fabric under plants can also provide much of the same protection, and allows water to drain through and away from leaves.

If All Else Fails…

Sometimes, cool and wet spring weather makes it impossible to prevent the onset of powdery mildew.

The first line of defense is to remove and destroy leaves that show the first signs of the tell-tale white spots. Removing them quickly can help keep the fungus from spreading.

Be sure to discard the leaves and keep them clear of the compost pile to avoid spreading the spores.

Using Milk Spray To Combat Powdery Mildew

If you are looking for an all-natural solution, good old-fashioned milk can help.

milk spray on plants
A 50-50 solution of milk and water sprayed onto the leaves can help keep the disease at bay.

A 50% solution of milk and water applied to the plant’s foliage once a week, or after a heavy rain can help prevent onset of the disease.

Begin applying once the first few leaves begin to form on plants in early spring, and continue until early summer.

For more on growing cucumbers, check out our article : 6 Great Tips For Growing A Banner Crop Of Cucumbers.

Here is to keeping your cucumber plants healthy and strong this year!

This Is My Garden is a website dedicated to spreading the love and knowledge of gardening around the world. We publish two new garden articles each week. This article may contain affiliate links.

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