One of the first steps you take when you are getting a good idea 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.

It's possible to figure out when to plant catharanthus by referring to the USDA zone info for Powell.

Planting Calendar for Catharanthus

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

Since catharanthus are not cold tolerant it's important to wait until after the last frost before you can plant them.

The earliest that you can plant catharanthus in Powell 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 few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Powell. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Powell is just an average the actual date of last frost is different every year. Half of the time in Powell you get surprised by a frost after April 15 so always be ready to protect your catharanthus in the event of one of those late frosts.

USDA Zone Info for Powell

Here is the info for USDA Zone 6a.

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

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Powell

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