One of the best tools that you have as gardeners to help us determine 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 first chance to plant helianthemum in Lowell can be determined by using the USDA zone info.

Planting Calendar for Helianthemum

Frost tolerance for helianthemum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since helianthemum are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant helianthemum 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 helianthemum and expect a good harvest is probably September. If you wait any later than that and your helianthemum may not have a chance to really do well. You can get started a couple of weeks earlier by starting your helianthemum indoors.

Last Frost Date

In Lowell the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that USDA zone info for Lowell is just an average and the actual date of last frost changes from year to year. Since half of the time in Lowell it frosts late in the year after April 15 be ready to cover your helianthemum if you have one of those late frosts.

USDA Zone Info for Lowell

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 Lowell

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