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.

A way of getting a good idea when it's a good idea to plant helianthemum is to use the USDA zone info for Post Falls.

Planting Calendar for Helianthemum

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

Helianthemum can survive in mild cold which tells us that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant helianthemum in Post Falls 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. Any later than that and your helianthemum may not have a chance to fully mature. You can get started a little bit earlier by starting your helianthemum indoors.

Last Frost Date

The average date of last frost is April 15 in Post Falls. In the coldest months of winter you can expect an average low temperature of -5°F.

Just be sure to remember that USDA zone info for Post Falls is just an average and the actual date of last frost is different every year. Half of the time in Post Falls there is a last frost after April 15 so make sure that you are prepared to protect your helianthemum in the event of one of those late frosts.

USDA Zone Info for Post Falls

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Post Falls

You may be interested in your other planting guides for Post Falls.