One of the first steps you take when you are making a decision about 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.

The best time to plant saxifraga in Cambridge can be figured out by referring to the USDA zone info.

Planting Calendar for Saxifraga

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

Saxifraga do ok in mild cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

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

Last Frost Date

On average the last frost is on May 15 in Cambridge. You should expect an average low temperature of -30°F in the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Cambridge and it will vary from year to year. Since half of the time in Cambridge it frosts late in the year after May 15 be ready to cover your saxifraga in the event of 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.