When Is the Right Time to Plant Cucumbers in Illinois?

Do you love cucumbers and want to plant them in your Illinois garden this year? If so, you have come to the right place. Today, you will learn which parts of the state cucumbers thrive best and when to plant them.


USDA Plant Hardiness Zones Illinois

when to plant cucumbers in Illinois

The first step in determining when to plant cucumbers in Illinois is knowing the plant hardiness zone in your area. USDA hardiness zones will help you determine which types of vegetables and fruits will do well in your area. Because the state of Illinois is in different hardiness zones, you will have to find the right one for your local area. Below is a hardiness guide for each part of the state.

Northern Illinois

If you’re gardening in the northern part of the state, your hardiness zone will fall between zone 5a and zone 5b. In these zones, you will have an average minimum temperature of –20 to –15 degrees. Plants that do well in these zones are radish, apples, plums, and lavender to name a few.

You might notice that cucumbers did not make this list. This is because most cucumber varieties require a zone of 7 to 8 to thrive. However, if you live in this part of the state, your dreams of growing cucumbers are not lost. If you have a small to medium-sized greenhouse, you can easily grow cucumbers during the summer growing season.

Central Illinois

The central part of the state has two different hardiness zones due to its size. These zones are 5a and 6a. It has an average minimum temperature of –20 to –5 degrees. Things that grow well in this part of the state include bush beans, winter squash, and a variety of herbs. Planting cucumbers outside in this part of the state is possible, but they will do best when grown inside of a greenhouse.

Southern Illinois

Southern Illinois is the perfect place to plant cucumbers during the spring and summer months. This part of the state is in the USDA hardiness zones of 6a to 7a. This area of the state has an average minimum low-temperature range of –10 to 5 degrees. Cucumbers can be planted directly in the garden and will thrive with the right amount of water and nutrients.


Get Ahead by Starting Seeds Indoors

when to plant cucumbers in Illinois

Because Illinois is in the northern part of the country, you will have a shorter growing season. To get ahead of the season, you should consider starting your cucumbers indoors. This can easily be done, and it will give you an advantage in the garden.

Once you have found the perfect cucumber variety to plant for your area, you should start them indoors. The best way to start seeds indoors is by using a compostable growing tray. This will allow you to directly plant your seedlings into the ground without destroying the root system.


When To Transplant Seedlings to the Garden

when to plant cucumbers in Illinois

Once you have established healthy plants indoors, you should make plans to transplant them into the garden. But many gardeners have a difficult time finding out the perfect time to transplant. If you’re wondering when to plant cucumbers in Illinois, you should find out when the last average frost in your area is. Once you know when the last day of frost is, you can safely plant your cucumbers 10 to 14 days after this date.

In the northern and central parts of the state, the last day of frost normally occurs during the start of May. In the southern parts of the state, the last day of frost is during the last few days of April. To determine your exact frost date, you can use your zip code.

Use Plenty of Mulch

If you are planting cucumbers in your garden this year, make sure to provide them with plenty of mulch. Cucumbers thrive in organic-rich soils and giving them a good share of mulch will help keep them healthy. Mulch also locks in moisture and prevents plants from drying out. This will reduce the amount of water you will have to provide.

Watch Out for Disease and Pests

No matter if you are growing cucumber in the greenhouse or the garden, you will need to keep an eye out for pests and diseases. Some of the common pests that plague cucumbers are cutworms, cucumber beetles, aphids, and cabbage loopers.

Cucumber plants are also prone to certain diseases including, bacterial wilt, powdery mildew, and downy mildew.


When to plant cucumbers in Illinois: Conclusion

Now that you know how and when to plant cucumbers in Illinois, why not get started today? Having fresh cucumbers to eat during the summer months is a real treat.

Related Article: Cucumber Plant Growth Stages