The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. 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 Rockton can be looked at to estimate when it's the best time to plant primroses.

Planting Calendar for Primroses

Frost tolerance for primroses:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Primroses tend to make it in pretty solid cold which means that you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant primroses in Rockton 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 primroses and expect a good harvest is probably September. Any later than that and your primroses may not have a chance to really do well. Starting your primroses indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Rockton the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Rockton is not always accurate the actual date of last frost is different every year. Since half of the time in Rockton there is a last frost after April 15 be ready to cover your primroses if you have a surprise late frost.

USDA Zone Info for Rockton

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Rockton

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