One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

The USDA zone info for Petersburg should be read to figure out when to plant lupine.

Planting Calendar for Lupine

Frost tolerance for lupine:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Lupine are one of those plants that can tolerate a little bit of cold weather which tells us that you can get them planted earlier than more sensitive plants.

The earliest that you can plant lupine in Petersburg 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 lupine and expect a good harvest is probably September. Any later than that and your lupine may not have a chance to grow to maturity. Starting your lupine indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Petersburg. In the coldest months of winter you should expect an average low temperature of 5°F.

Since the USDA zone info for Petersburg is not always accurate the actual date of last frost will vary from year to year. Half of the time in Petersburg last frost occurs after April 15 so always be ready to protect your lupine 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.