One of the best tools that you have as gardeners to help us estimate 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.

One way of getting a good idea when you can plant primula is to refer to the USDA zone info for Bloomington.

Planting Calendar for Primula

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

Primula do well in cold which means that you can start planting them much earlier than other plants that might not handle the cold.

The earliest that you can plant primula in Bloomington 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 primula and expect a good harvest is probably September. If you wait any later than that and your primula may not have a chance to grow to maturity. Starting your primula indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Bloomington is an average and the actual date of last frost will vary from year to year. Half of the time in Bloomington it frosts late in the year after April 15 so just be sure to be ready to cover your primula if you have a surprise late frost.

USDA Zone Info for Bloomington

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 Bloomington

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