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

The USDA zone info for Dayton should be looked at to estimate when it's possible 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 do not do well in cold weather which means that you must wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant heliotrope in Dayton 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 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 grow to maturity. If you are starting your heliotrope indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Dayton. It might get as low as -25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Dayton and it can change quite a bit from year to year. Since half of the time in Dayton you get a frost after May 15 be ready to protect your heliotrope in the event of one of those late frosts.

USDA Zone Info for Dayton

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Dayton

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