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.

The USDA zone info for Half Moon Bay should be read to estimate when it's possible to plant alternanthera.

Planting Calendar for Alternanthera

Frost tolerance for alternanthera:	Not tolerant of frost.
When to plant:	After the last frost.

Since alternanthera require warm weather it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant alternanthera in Half Moon Bay 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 alternanthera and expect a good harvest is probably September. You probably don't want to wait any later than that or else your alternanthera may not have a chance to fully mature. If you are starting your alternanthera indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in Half Moon Bay. In the coldest months of winter you can expect an average low temperature of 30°F.

Since the USDA zone info for Half Moon Bay may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Half Moon Bay you get a frost after January 31 be ready to cover your alternanthera if you have a late frost.

USDA Zone Info for Half Moon Bay

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 Half Moon Bay

You may be interested in your other planting guides for Half Moon Bay.