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

It's possible to determine when to plant primroses by checking out the USDA zone info for Sterling Heights.

Planting Calendar for Primroses

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

Since primroses are very cold tolerant you can plant them much earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant primroses in Sterling Heights 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 grow to maturity. If you are starting your primroses indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Sterling Heights. In the coldest months of winter you should expect an average low temperature of -10°F.

It's important to remember that USDA zone info for Sterling Heights may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Sterling Heights you get a frost after April 15 so just be sure to be ready to protect your primroses in the event of a surprise late frost.

USDA Zone Info for Sterling Heights

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Sterling Heights

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