One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's a good idea to plant campanula by looking at the USDA zone info for Sterling Heights.

Planting Calendar for Campanula

Frost tolerance for campanula:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since campanula do well in moderate cold you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant campanula 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 campanula and expect a good harvest is probably September. Any later than that and your campanula may not have a chance to grow to maturity. If you are starting your campanula 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. You should expect an average low temperature of -10°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Sterling Heights and it will vary from year to year. Since half of the time in Sterling Heights you get surprised by a frost after April 15 be ready to protect your campanula if you have 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.