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

By looking at the USDA zone info for Alma it's a good idea to estimate when it's possible to plant helianthemum.

Planting Calendar for Helianthemum

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

Helianthemum do well in moderate cold which tells us that you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant helianthemum in Alma 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 fully mature. If you are starting your helianthemum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Alma. In the coldest months of winter you can expect an average low temperature of -10°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Alma and it will vary from year to year. Since half of the time in Alma it frosts late in the year after April 15 be ready to cover your helianthemum in the event of a surprise late frost.

USDA Zone Info for Alma

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 Alma

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