Before planting it is a good idea to find your USDA Zone info to estimate your garden 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 Sulphur should be used to determine when it's a good idea 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 are moderately cold tolerant which tells us that you can plant them earlier than other frost tender plants.

The earliest that you can plant campanula in Sulphur 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 really do well. Starting your campanula indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Sulphur. It might get as low as 5°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Sulphur is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Sulphur there is a last frost after April 15 so make sure that you are prepared to protect your campanula if you have a late frost.

USDA Zone Info for Sulphur

Here is the info for USDA Zone 7b.

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

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

Plants to Grow in Sulphur

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