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

The first chance to plant helianthemum in Inverness can be figured out by referring to 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 do well in moderate cold you can plant them a little bit earlier in the year than other frost tender plants.

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

The last month that you can plant helianthemum and expect a good harvest is probably October. If you wait any later than that and your helianthemum may not have a chance to really do well. Starting your helianthemum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Inverness. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Inverness is an average the actual date of last frost will vary from year to year. Half of the time in Inverness it frosts late in the year after February 15 so make sure that you are prepared to cover your helianthemum in the event of a surprise late frost.

USDA Zone Info for Inverness

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Inverness

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