One of the first steps you take when you are determining your gardening schedule is find your 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 getting a good idea when to plant primroses is to check out the USDA zone info for Cambridge.

Planting Calendar for Primroses

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

Primroses can survive in quite a bit of cold which tells us that you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant primroses in Cambridge 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

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

Since the USDA zone info for Cambridge is just an average the actual date of last frost changes from year to year. Half of the time in Cambridge last frost occurs after April 15 so be sure to be ready to cover your primroses if you have a surprise late frost.

USDA Zone Info for Cambridge

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 Cambridge

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