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

You should be able to determine when it's a good idea to plant heliotrope by using the USDA zone info for Grapevine.

Planting Calendar for Heliotrope

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

Heliotrope require warm weather which tells us that you need to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant heliotrope in Grapevine 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 really do well. If you are starting your heliotrope indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Grapevine. You should expect an average low temperature of 10°F in the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Grapevine and it changes from year to year. Since half of the time in Grapevine you get a frost after March 15 be ready to protect your heliotrope in the event of one of those late frosts.

USDA Zone Info for Grapevine

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 Grapevine

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