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

A common way of figuring out when to plant blue lace flowers is to use the USDA zone info for Cambridge.

Planting Calendar for Blue Lace Flowers

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

Blue Lace Flowers are barely cold tolerant which tells us that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant blue lace flowers in Cambridge is April. However, you really should wait until May if you don't want to take any chances.

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

Last Frost Date

The average date of last frost is May 15 in Cambridge. In the coldest months of winter you should expect an average low temperature of -30°F.

Since the USDA zone info for Cambridge is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Cambridge it frosts late in the year after May 15 so be sure to be ready to protect your blue lace flowers if you have a late frost.

USDA Zone Info for Cambridge

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Cambridge

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