Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Simi Valley you can figure out when you can plant helianthemum by looking at 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.

Helianthemum can survive in moderate cold which means that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant helianthemum in Simi Valley 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 fully mature. You can get started a few weeks earlier by starting your helianthemum indoors.

Last Frost Date

In Simi Valley the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Simi Valley and it can change quite a bit from year to year. Since half of the time in Simi Valley it frosts late in the year after February 15 be ready to cover your helianthemum in the event of a late frost.

USDA Zone Info for Simi Valley

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Simi Valley

You may be interested in your other planting guides for Simi Valley.