One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for San Mateo should be used to determine when it's a good idea to plant argyranthemum.

Planting Calendar for Argyranthemum

Frost tolerance for argyranthemum:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant argyranthemum until after the last frost because they do not do well in cold weather.

The earliest that you can plant argyranthemum in San Mateo 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 argyranthemum and expect a good harvest is probably September. Any later than that and your argyranthemum may not have a chance to really do well. Starting your argyranthemum indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In San Mateo the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for San Mateo is not always accurate the actual date of last frost is different every year. Since half of the time in San Mateo you get a frost after January 31 be ready to cover your argyranthemum 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.