One of the first steps you take when you are making a decision about your gardening schedule is find your 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 estimate when it's the best time to plant heliotrope by looking at the USDA zone info for Leominster.

Planting Calendar for Heliotrope

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

Since heliotrope require warm weather you must wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant heliotrope in Leominster 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 really do well. You can get started a little bit earlier by starting your heliotrope indoors.

Last Frost Date

In Leominster the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Leominster is an average and the actual date of last frost will vary from year to year. Half of the time in Leominster it frosts late in the year after April 15 so be sure to be ready to cover your heliotrope in the event of one of those late frosts.

USDA Zone Info for Leominster

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 Leominster

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