One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of figuring out when it's a good idea to plant mustard is to use the USDA zone info for Petersburg.

Planting Calendar for Mustard

Frost tolerance for mustard:	Not tolerant of frost.
When to plant:	After the last frost.

Since mustard do not do well in cold weather it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant mustard 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 mustard and expect a good harvest is probably August. If you wait any later than that and your mustard may not have a chance to grow to maturity. If you are starting your mustard indoors then you might be able to get away with starting them a couple of weeks earlier.

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 will vary from year to year. Since half of the time in Petersburg it frosts late in the year after April 15 be ready to protect your mustard if you have a surprise 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.