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How To Keep Cucumber Plants Safe From Pests & Disease

Looking for the secrets to success when it comes to keeping your cucumber plants safe from the perils of disease and pests?

Aside from tomatoes, cucumbers are the second most widely grown vegetable in home gardens. They are also one of the most versatile vegetables around when it comes to being used in your kitchen. 

But no matter how you use your cucumbers, it can often be quite the challenge to grow a sizable harvest from your plants. From mold, mildew and disease issues, to a slew of pest problems and more, cucumbers tend have a history of frustrating even the most seasoned gardener. 

Protecting vegetables with supports.
Keeping your plants safe from disease and pests is one of the best ways to ensure a great harvest of fresh cucumbers.

But the good news is that it doesn’t have to be difficult to grow an amazing harvest of cucumbers! Nor does the effort have to be a time-consuming. In fact, armed with just a few key planting and growing tips, you can all but ensure strong and healthy plants – and a great harvest!

How To Keep Cucumber Plants Safe From Pests & Disease

Planting Location 

One of the biggest factors in keeping your cucumber plants safe and productive happens before you ever place a seed or plant into the soil. And that factor is picking the proper planting location.

There are a few things to keep in mind when choosing your growing location for your cucumber plants, the first of which is keeping good sunlight in mind. Cucumber plants need a lot of sunlight in order to grow and produce fruit. Especially early morning sun.

Powdery mildew covering green leaves on a plant - How To Keep Cucumber Plants Safe From Pests & Disease
One of the biggest diseases to hit cucumber plants is powdery mildew. Once it appears, it can quickly overtake otherwise healthy plants. But locating your cucumbers where early morning sun can dry their leaves can greatly reduce the chance of mildew occurring.

Not only does a lack of sunlight set the stage for plants to fail to thrive and produce, it also leaves them more susceptible to powdery mildew. Powdery mildew is one of the most common yet destructive diseases that can affect cucumber plants. 

If left unchecked, it will drastically reduce fruit production and the health of existing foliage. If bad enough, it is also often fatal to cucumber plants altogether.

What Causes Powdery Mildew & Mold

So what is the root cause of powdery mildew? One of the biggest contributors is when plants have too much moisture on their foliage for extended periods of time. If cucumber plants sit in the shade, especially during the morning hours, the moisture built up from the morning dew can quickly lead to mildew and mold issues.

To help alleviate this issue, always try to plant your cucumbers in a location the receives at least 8 hours of sunlight. Also, avoid watering plants overhead. Unfortunately, this added moisture on foliage can also aid in the formation of powdery mildew. Finally, always water plants early in the morning to allow them time to dry out throughout the day.

Giving Your Plants The Soil They Need For Success – How To Keep Cucumber Plants Safe From Pests & Disease

Having healthy and nutrient filled soil will go a long way in keeping your cucumber plants growing strong and avoiding trouble. Weak, struggling plants are an easy target for both pests and disease to take hold.

Cucumbers need loose, well-draining soil in order to help in the fight against powdery mildew. If the growing location area and soil cannot drain away excess water, it leaves plants susceptible of not just mildew, but rot as well.

Proper soil is important to the health of your cucumber plants.
Before planting your seeds or transplants, be sure to amend the soil with plenty of compost. This will help with better drainage and energize the soil at the same time.

For starters, always plant you cucumbers in slight hills. This will shed excess water around the main stems. In addition, be sure to add a good amount of compost to each planting area. Amending with compost will help increase drainage and add all-important nutrients.

The compost helps to add channels and air pockets within the soil. In turn, this creates more places for the water to travel to as opposed to just sitting on top. If you happen to have extremely heavy, clay-like soil, you can also mix in sand and/or perlite to increase drainage even more.

Adding Mulch – How To Keep Cucumber Plants Safe From Pests & Disease

Now that you have chosen the perfect planting location with plenty of fertile soil and sunlight, the next step for healthier plants and blemish-free cucumbers is mulching.

A bunch of straw being put around cucumber plants
Add plenty of mulch around your cucumber plants to help keep fruit off the bare soil and to help reduce weeds.

Adding an all-natural mulch like straw, shredded leaves, or grass clippings underneath plants is a must to keep weeds, pests and disease away from plant.

When weeds grow around cucumber plants, they compete for nutrients and resources within the soil. The mulch helps to block out those competing weeds from establishing. Even more, mulch helps to regulate the soil temperature and keep a healthy amount of moisture in the roots. 

In addition, mulch helps to keep foliage and blooms clean and disease free. When plants lay directly on the soil, it’s easy for soil-born diseases to take root and make themselves at home. It also helps prevent pests like slugs and cucumber beetles from easily finding plants. 

Once plants have started to emerge from the soil, add about four to six inches of natural mulch all around the plants. Leave about an inch or two around the base of each stem to prevent the mulch from touching the plant. This will keep the main stem from having too much moisture and rotting.

Spacing & Supports – How To Keep Cucumber Plants Safe From Pests & Disease

Cucumbers come in two main growing varieties: Bush and Vining. Depending on which you grow, providing support for them can both help against disease and pests. Bush plants are more compact and mounding in formation. They are excellent for containers or smaller garden spaces. (Product Link: Spacemaster Bush Cucumber Seeds)

How To Keep Cucumber Plants Safe From Pests & Disease
Trellises are needed to help keep vining cucumbers off the soil and away from pests and diseases.

Bush varieties don’t really need additional support, but be sure to keep plants properly spaced apart when planting. Growing them too close together will increase the chances of contracting diseases or attracting pests. 

Vining cucumber varieties tend to produce more fruit, but need to have support to keep their long vines from sprawling on open soil. The good news is that vining cucumber plants send out tendrils that grab onto nearby plants or supports to help them climb. (Product Link: Boston Pickling Cucumber Seeds)

Since allowing plants to grow along the soil can expose them more easily to pests and soil-born diseases, allowing them to train vertically on a support can help keep them safe. It also happens to save big on available garden space too! Trellises, arbors, or even fence lines will all work well to support cucumbers.

Using a support will keep the foliage and fruit up off of the soil and allow increased airflow to plants. Having proper airflow also helps to reduce the chances of plants ending up with powdery mildew. 

Avoiding Pests – How To Keep Cucumber Plants Safe From Pests & Disease

When it comes to pests, cucumbers have a whole host of insects that enjoy cucumber plants as much as you do. Because of that, adding some protection for your plants is important!

For starters, growing a few companion plants around your growing cucumbers can help in the fight. Marigolds and Nasturtiums are both great examples of a companion plant for cucumbers. They help to attract beneficial pollinators like butterflies and bees while repelling unwanted pests like aphids and nematodes. 

 How To Keep Cucumber Plants Safe From Pests & Disease
This cucumber beetle is not a pest you want to see around your plants!

Cucumber beetles are another pest that can hit cucumber plants hard. They arrive in late May and June and can cause great destruction to the foliage and flowers of cucumber plants. Even worse, their bite on the plants can bring on bacterial wilt, which will slowly kill the entire plant.

Planting trap crops like sweet alyssum nearby, which they prefer more, can attract the beetles away from you plants. Neem oil is another option to spray if beetles are present.

Perhaps the best way of all to protect plants is with plant covers in mid-May to early June when the beetles arrive. The plants are small at this point and covering them can keep them safe from the beetles until they leave by mid summer. For more, see on cucumber beetles, check out our article “How To Eliminate Cucumber Beetles

Here is to protecting your plants before and after they go in the ground. And – to a great harvest of cucumbers this year!

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