Before planting it is a good idea to find your USDA Zone info to determine your garden 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 to plant alyssum is to look at the USDA zone info for Palo Alto.

Planting Calendar for Alyssum

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

You can plant alyssum quite a bit earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant alyssum in Palo Alto 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. You probably don't want to wait any later than that or else your alyssum may not have a chance to really do well. If you are starting your alyssum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Palo Alto the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Palo Alto is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Palo Alto it frosts late in the year after February 15 be ready to protect your alyssum if you have a surprise late frost.

USDA Zone Info for Palo Alto

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 Palo Alto

You may be interested in your other planting guides for Palo Alto.