When to Plant Primroses in Harvard, 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.

The first chance to plant primroses in Harvard should be determined by reviewing the USDA zone info.


Planting Calendar for Primroses

Frost tolerance for primroses: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Since primroses do well in cold you can plant them quite a bit earlier in the year than plants that are more sensitive to the cold.

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

The earliest that you can plant primroses in Harvard 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 primroses and expect a good harvest is probably September. Any later than that and your primroses may not have a chance to fully mature. Starting your primroses indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Harvard the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Harvard is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Harvard it frosts late in the year after April 15 so make sure that you are prepared to protect your primroses in the event of one of those late frosts.

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.