One of the best tools that you have as gardeners to help us determine 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.

In Olyphant you can estimate when you can plant catharanthus by reviewing the USDA zone info.

Planting Calendar for Catharanthus

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

You should not plant catharanthus until after the last frost because they are not cold tolerant.

The earliest that you can plant catharanthus in Olyphant 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 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 all chance of frost has passed is on April 15 in Olyphant. You can expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Olyphant and it is different every year. Half of the time in Olyphant you get surprised by a frost after April 15 so always be ready to cover your catharanthus in the event of one of those late frosts.

USDA Zone Info for Olyphant

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 Olyphant

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