The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's the best time to plant alyssum is to use the USDA zone info for Los Altos.

Planting Calendar for Alyssum

Frost tolerance for alyssum:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Alyssum are one of those plants that can tolerate quite a bit of cold weather which means that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant alyssum in Los Altos 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 alyssum and expect a good harvest is probably October. Any later than that and your alyssum may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your alyssum indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Los Altos. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that USDA zone info for Los Altos is an average and the actual date of last frost is different every year. Half of the time in Los Altos there is a last frost after February 15 so just be sure to be ready to protect your alyssum if you have one of those late frosts.

USDA Zone Info for Los Altos

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 Los Altos

You may be interested in your other planting guides for Los Altos.