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

The USDA zone info for South Portland can be reffered to in order to figure out when 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.

You can plant campanula a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant campanula in South Portland 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. If you wait any later than that and your campanula may not have a chance to fully mature. You can get started a few weeks earlier by starting your campanula indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in South Portland. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for South Portland is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in South Portland last frost occurs after April 15 so make sure that you are ready to protect your campanula in the event of a surprise late frost.

USDA Zone Info for South Portland

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 South Portland

You may be interested in your other planting guides for South Portland.