One of the first steps you take when you are determining your gardening schedule is find your 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.

By using the USDA zone info for Cambridge you will be able to estimate when it's a good idea to plant four o' clock.

Planting Calendar for Four O' Clock

Frost tolerance for four o' clock:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's not a good idea to plant four o' clock until after the last frost because they do not do well in cold weather.

The earliest that you can plant four o' clock 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 four o' clock and expect a good harvest is probably August. You probably don't want to wait any later than that or else your four o' clock may not have a chance to really do well. You can get started a little bit earlier by starting your four o' clock indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Cambridge. It might get as low as -5°F during the coldest months of winter.

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. Since half of the time in Cambridge you get surprised by a frost after April 15 be ready to cover your four o' clock if you have a 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.