One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when you can plant primroses is to use the USDA zone info for Mendota.

Planting Calendar for Primroses

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

Primroses do well in cold which means that you can plant them a quite a bit earlier than more sensitive plants.

The earliest that you can plant primroses in Mendota 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 little bit earlier.

Last Frost Date

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

Since the USDA zone info for Mendota is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Mendota you get surprised by a frost after April 15 so just be sure to be ready to protect your primroses in the event of one of those late frosts.

USDA Zone Info for Mendota

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 Mendota

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