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When to Plant Nierembergia in Harwood Heights, IL

One of the best tools that you have as gardeners to help us figure out 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.

You should be able to estimate when it's a good idea to plant nierembergia by reviewing the USDA zone info for Harwood Heights.


Planting Calendar for Nierembergia

Frost tolerance for nierembergia: Not tolerant of frost.
When to plant: After the last frost.

Since nierembergia are not cold tolerant it's important to wait until after all chance of frost has passed before you can plant them.

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

The earliest that you can plant nierembergia in Harwood Heights is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant nierembergia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your nierembergia may not have a chance to grow to maturity. If you are starting your nierembergia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Harwood Heights. It might get as low as -15°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Harwood Heights and it is different every year. Half of the time in Harwood Heights last frost occurs after April 15 so make sure that you are prepared to protect your nierembergia in the event of one of those late frosts.

USDA Zone Info for Harwood Heights

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 Harwood Heights

You may be interested in your other planting guides for Harwood Heights.