Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Cambridge you should be able to estimate when to plant celosia.

Planting Calendar for Celosia

Frost tolerance for celosia:	Not tolerant of frost.
When to plant:	After the last frost.

Since celosia are not cold tolerant you must wait until after all chance of frost has passed before you can plant them.

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

The last month that you can plant celosia and expect a good harvest is probably August. Any later than that and your celosia may not have a chance to really do well. You can get started a little bit earlier by starting your celosia indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Cambridge and it will vary from year to year. Half of the time in Cambridge it frosts late in the year after May 15 so make sure that you are ready to protect your celosia if you have 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.