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 Douglas you will be able to estimate when to plant petunias.

Planting Calendar for Petunias

Frost tolerance for petunias:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Petunias can survive in very little cold which means that you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant petunias in Douglas is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant petunias and expect a good harvest is probably August. You probably don't want to wait any later than that or else your petunias may not have a chance to really do well. If you are starting your petunias indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Douglas the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Douglas is an average the actual date of last frost changes from year to year. Since half of the time in Douglas you get surprised by a frost after May 15 be ready to protect your petunias in the event of one of those late frosts.

USDA Zone Info for Douglas

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Douglas

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