When to Plant Flower-of-an-Hour in Harvard, IL

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant flower-of-an-hour in Harvard can be estimated by reviewing the USDA zone info.


Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

You can plant flower-of-an-hour a bit earlier in the year because they are barely cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant flower-of-an-hour
Possibly ok, but a risky time to plant flower-of-an-hour
Probably not a good time to plant flower-of-an-hour

The earliest that you can plant flower-of-an-hour in Harvard is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant flower-of-an-hour and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flower-of-an-hour may not have a chance to really do well. You can get started a couple of weeks earlier by starting your flower-of-an-hour indoors.

Last Frost Date

In Harvard the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Harvard may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Harvard it frosts late in the year after April 15 be ready to cover your flower-of-an-hour if you have a surprise late frost.

USDA Zone Info for Harvard

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 Harvard

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