When to Plant Campanula in Swarthmore, PA

One of the first steps you take when you are estimating your gardening schedule is find your 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.

A way of determining when to plant campanula is to examine the USDA zone info for Swarthmore.


Planting Calendar for Campanula

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

Campanula are moderately cold tolerant which tells us that you can start planting them earlier than more sensitive plants.

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

The earliest that you can plant campanula in Swarthmore 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 couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Swarthmore. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Swarthmore is not always accurate the actual date of last frost changes from year to year. Since half of the time in Swarthmore you get surprised by a frost after April 15 be ready to protect your campanula in the event of one of those late frosts.

USDA Zone Info for Swarthmore

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 Low0°F
Highest Expected Low5°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 Swarthmore

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