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

You can estimate when to plant helianthemum in San Mateo by checking out 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 do well in some cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant helianthemum in San Mateo 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 little bit earlier by starting your helianthemum indoors.

Last Frost Date

On average the last frost has passed is on January 31 in San Mateo. It might get as low as 30°F during the coldest months of winter.

Just be sure to remember that USDA zone info for San Mateo may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in San Mateo there is a last frost after January 31 so be sure to be ready to protect your helianthemum in the event of one of those late frosts.

USDA Zone Info for San Mateo

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in San Mateo

You may be interested in your other planting guides for San Mateo.