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

A way of determining when it's a good idea to plant amaranthus is to look at the USDA zone info for Portola Valley.

Planting Calendar for Amaranthus

Frost tolerance for amaranthus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since amaranthus are not cold tolerant it is important to wait until after the last frost has passed before you can plant them.

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

Last Frost Date

On average the last frost is on January 31 in Portola Valley. You should expect an average low temperature of 30°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Portola Valley and it changes from year to year. Since half of the time in Portola Valley you get surprised by a frost after January 31 be ready to protect your amaranthus in the event of one of those late frosts.

USDA Zone Info for Portola Valley

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 Portola Valley

You may be interested in your other planting guides for Portola Valley.