One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to estimate when it's possible to plant alternaria by referring to the USDA zone info for Atherton.

Planting Calendar for Alternaria

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

Since alternaria do not do well in cold weather you have to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant alternaria in Atherton is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant alternaria and expect a good harvest is probably September. If you wait any later than that and your alternaria may not have a chance to fully mature. You can get started a little bit earlier by starting your alternaria indoors.

Last Frost Date

The average date of last frost is February 15 in Atherton. In the coldest months of winter you can expect an average low temperature of 25°F.

It's important to remember that USDA zone info for Atherton is an average and the actual date of last frost is different every year. Since half of the time in Atherton it frosts late in the year after February 15 be ready to cover your alternaria if you have a surprise late frost.

USDA Zone Info for Atherton

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 Atherton

You may be interested in your other planting guides for Atherton.