Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when to plant helianthemum is to consult the USDA zone info for Greenfield.

Planting Calendar for Helianthemum

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

Helianthemum are one of those plants that can tolerate a little bit of cold weather which means that you can plant them a little bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant helianthemum in Greenfield 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 little bit earlier by starting your helianthemum indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Greenfield and it is different every year. Half of the time in Greenfield last frost occurs after April 15 so make sure that you are prepared to protect your helianthemum in the event of a surprise late frost.

USDA Zone Info for Greenfield

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 Greenfield

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