One of the first steps you take when you are determining 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.

By looking at the USDA zone info for Westminster it's possible to figure out when it's the best time to plant campanula.

Planting Calendar for Campanula

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

Campanula do ok in mild cold which means that you can plant them just a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant campanula in Westminster 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. You probably don't want to wait any later than that or else your campanula may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your campanula indoors.

Last Frost Date

In Westminster the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Westminster may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Westminster it frosts late in the year after April 15 so always be ready to cover your campanula if you have a surprise late frost.

USDA Zone Info for Westminster

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Westminster

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