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.

The earliest that you can plant purple coneflower in Cambridge should be estimated by looking at the USDA zone info.

Planting Calendar for Purple Coneflower

Frost tolerance for purple coneflower:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant purple coneflower a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant purple coneflower in Cambridge is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant purple coneflower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your purple coneflower may not have a chance to fully mature. If you are starting your purple coneflower indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Cambridge the average date of last frost happens on April 15. It might get as low as -5°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Cambridge is just an average and the actual date of last frost is different every year. Half of the time in Cambridge it frosts late in the year after April 15 so be sure to be ready to cover your purple coneflower if you have a surprise late frost.

USDA Zone Info for Cambridge

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Cambridge

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