One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's possible to plant catharanthus in Oak Ridge by looking at the USDA zone info.

Planting Calendar for Catharanthus

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

It's probably a bad idea to plant catharanthus until after the last frost has passed because they require warm weather.

The earliest that you can plant catharanthus in Oak Ridge 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. If you wait any later than that and your catharanthus may not have a chance to grow to maturity. Starting your catharanthus indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Oak Ridge. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Oak Ridge is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Oak Ridge it frosts late in the year after April 15 be ready to cover your catharanthus in the event of a late frost.

USDA Zone Info for Oak Ridge

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Oak Ridge

You may be interested in your other planting guides for Oak Ridge.