Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Cambridge you can figure out when it's a good idea to plant catharanthus by referring to the USDA zone info.

Planting Calendar for Catharanthus

Frost tolerance for catharanthus:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You can not plant catharanthus until after the last frost when the weather gets warmer because they are not cold tolerant.

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

Last Frost Date

On average the last frost has passed is on April 15 in Cambridge. You can expect an average low temperature of 5°F in the coldest months of winter.

Since the USDA zone info for Cambridge may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Cambridge it frosts late in the year after April 15 be ready to cover your catharanthus in the event of a surprise late frost.

USDA Zone Info for Cambridge

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Cambridge

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