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 first opportunity to plant alternaria in Petersburg should be determined by checking out the USDA zone info.

Planting Calendar for Alternaria

Frost tolerance for alternaria:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since alternaria do not do well in cold weather you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant alternaria in Petersburg 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 alternaria and expect a good harvest is probably August. If you wait any later than that and your alternaria may not have a chance to fully mature. You can get started a few weeks earlier by starting your alternaria indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Petersburg. It might get as low as 5°F during the coldest months of winter.

Since the USDA zone info for Petersburg is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Petersburg there is a last frost after April 15 be ready to cover your alternaria if you have a late frost.

USDA Zone Info for Petersburg

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 Petersburg

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