Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 heliotrope in Mount Vernon should be figured out by using the USDA zone info.

Planting Calendar for Heliotrope

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

Heliotrope require warm weather which tells us that it's important to 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 Mount Vernon 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. Starting your heliotrope indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Mount Vernon. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to 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 Mount Vernon and it can change quite a bit from year to year. Since half of the time in Mount Vernon there is a last frost after April 15 be ready to cover your heliotrope in the event of a surprise late frost.

USDA Zone Info for Mount Vernon

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Mount Vernon

You may be interested in your other planting guides for Mount Vernon.