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

You can estimate when to plant alyssum in Cambridge by looking at the USDA zone info.

Planting Calendar for Alyssum

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

Alyssum are one of those plants that can tolerate quite a bit of cold weather which means that you can start planting them much earlier than other frost tender plants.

The earliest that you can plant alyssum 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 alyssum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your alyssum may not have a chance to grow to maturity. Starting your alyssum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Cambridge and it changes from year to year. Half of the time in Cambridge there is a last frost after May 15 so always be ready to cover your alyssum in the event of a surprise 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.