The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Lowell can be looked at to figure out when it's the best time to plant liatris.

Planting Calendar for Liatris

Frost tolerance for liatris:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since liatris are very cold tolerant you can plant them a lot earlier in the year than more sensitive plants.

The earliest that you can plant liatris in Lowell is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant liatris and expect a good harvest is probably September. Any later than that and your liatris may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your liatris indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Lowell. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Lowell may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Lowell there is a last frost after April 15 so just be sure to be ready to protect your liatris in the event of a late frost.

USDA Zone Info for Lowell

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Lowell

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