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

The USDA zone info for Fairbanks should be used to determine when you can plant catharanthus.

Planting Calendar for Catharanthus

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

It's probably not a good idea to plant catharanthus until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant catharanthus in Fairbanks 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 catharanthus and expect a good harvest is probably August. Any later than that and your catharanthus may not have a chance to really do well. 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 is on May 15 in Fairbanks. In the coldest months of winter you should expect an average low temperature of -50°F.

Since the USDA zone info for Fairbanks is just an average the actual date of last frost changes from year to year. Since half of the time in Fairbanks it frosts late in the year after May 15 be ready to protect your catharanthus if you have a late frost.

USDA Zone Info for Fairbanks

Here is the info for USDA Zone 2a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	August 15
Lowest Expected Low	-50°F
Highest Expected Low	-45°F

This means that on a really cold year, the coldest it will get is -50°F. On most years you should be prepared to experience lows near -45°F.

Plants to Grow in Fairbanks

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