One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when it's possible to plant helianthemum is to consult the USDA zone info for Modesto.

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 plants that might not handle the cold.

The earliest that you can plant helianthemum in Modesto 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 grow to maturity. You can get started a few weeks earlier by starting your helianthemum indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Modesto. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Modesto may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Modesto you get surprised by a frost after February 15 so make sure that you are ready to cover your helianthemum in the event of a late frost.

USDA Zone Info for Modesto

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 Modesto

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