The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Blue Island you can determine when it's the best time to plant primroses by looking at the USDA zone info.

Planting Calendar for Primroses

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

Primroses are very cold tolerant which means that you can plant them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant primroses in Blue Island 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 grow to maturity. You can get started a couple of weeks earlier by starting your primroses indoors.

Last Frost Date

The average date of last frost is April 15 in Blue Island. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Blue Island may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Blue Island last frost occurs after April 15 be ready to cover your primroses in the event of a surprise late frost.

USDA Zone Info for Blue Island

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Blue Island

You may be interested in your other planting guides for Blue Island.