When to Plant Kohlrabi in Ottawa, IL

One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of figuring out when it's the best time to plant kohlrabi is to refer to the USDA zone info for Ottawa.

Create beautiful hand-made plants at forever-plants.com

Planting Calendar for Kohlrabi

Frost tolerance for kohlrabi: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Since kohlrabi are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant kohlrabi
Possibly ok, but a risky time to plant kohlrabi
Probably not a good time to plant kohlrabi

The earliest that you can plant kohlrabi in Ottawa is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant kohlrabi and expect a good harvest is probably September. If you wait any later than that and your kohlrabi may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your kohlrabi indoors.

Last Frost Date

On average the last frost is on April 15 in Ottawa. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Ottawa is an average the actual date of last frost will vary from year to year. Since half of the time in Ottawa it frosts late in the year after April 15 be ready to protect your kohlrabi if you have a surprise late frost.

USDA Zone Info for Ottawa

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Ottawa

You may be interested in your other planting guides for Ottawa.