One of the first steps you take when you are figuring out 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.

The USDA zone info for Alpharetta should be used to estimate when it's the best time 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.

Since petunias do ok in moderate cold 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 Alpharetta is March. However, you really should wait until April 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 fully mature. If you are starting your petunias indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Alpharetta. It might get as low as 5°F during the coldest months of winter.

Always keep in mind that USDA zone info for Alpharetta is just an average and the actual date of last frost changes from year to year. Since half of the time in Alpharetta there is a last frost after April 15 be ready to protect your petunias in the event of one of those late frosts.

USDA Zone Info for Alpharetta

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 Alpharetta

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