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.

The best time to plant catharanthus in Isanti can be determined by checking out the USDA zone info.

Planting Calendar for Catharanthus

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

Catharanthus are not cold tolerant which means that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant catharanthus in Isanti 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 grow to maturity. You can get started a few weeks earlier by starting your catharanthus indoors.

Last Frost Date

In Isanti the average date of last frost happens on May 15. You can expect an average low temperature of -30°F in the coldest months of winter.

Keep in mind that USDA zone info for Isanti may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Isanti there is a last frost after May 15 be ready to protect your catharanthus in the event of one of those late frosts.

USDA Zone Info for Isanti

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 Isanti

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