Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant heliotrope in Charles City should be determined by reviewing the USDA zone info.

Planting Calendar for Heliotrope

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

Since heliotrope are not cold tolerant it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant heliotrope in Charles City 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 heliotrope and expect a good harvest is probably August. Any later than that and your heliotrope may not have a chance to fully mature. You can get started a little bit earlier by starting your heliotrope indoors.

Last Frost Date

The average date of last frost is April 15 in Charles City. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Charles City is not always accurate the actual date of last frost is different every year. Half of the time in Charles City there is a last frost after April 15 so be sure to be ready to protect your heliotrope in the event of a late frost.

USDA Zone Info for Charles City

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Charles City

You may be interested in your other planting guides for Charles City.