One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant primula in Mokena can be estimated by referring to the USDA zone info.

Planting Calendar for Primula

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

Primula can survive in cold weather which tells us that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant primula in Mokena 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 primula and expect a good harvest is probably September. If you wait any later than that and your primula may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your primula indoors.

Last Frost Date

The average date of last frost is April 15 in Mokena. You can expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Mokena is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Mokena it frosts late in the year after April 15 so just be sure to be ready to protect your primula if you have a surprise late frost.

USDA Zone Info for Mokena

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 Mokena

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