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.

In Atherton you can figure out when to plant violas by reviewing the USDA zone info.

Planting Calendar for Violas

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

Since violas are very cold tolerant you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant violas in Atherton 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 violas and expect a good harvest is probably October. If you wait any later than that and your violas may not have a chance to grow to maturity. Starting your violas indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Atherton. In the coldest months of winter you should expect an average low temperature of 25°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Atherton and it changes from year to year. Since half of the time in Atherton you get a frost after February 15 be ready to cover your violas in the event of 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.