One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Irmo it's possible to determine when it's the best time to plant heliotrope.

Planting Calendar for Heliotrope

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

Heliotrope require warm weather which means that it is important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant heliotrope in Irmo 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. You probably don't want to wait any later than that or else your heliotrope may not have a chance to fully mature. You can get started a few weeks earlier by starting your heliotrope indoors.

Last Frost Date

The average date of last frost is March 15 in Irmo. In the coldest months of winter you should expect an average low temperature of 10°F.

Remember that USDA zone info for Irmo is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Irmo you get surprised by a frost after March 15 be ready to cover your heliotrope in the event of one of those late frosts.

USDA Zone Info for Irmo

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Irmo

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