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.

The first opportunity to plant impatiens in Sonoma should be estimated by referring to the USDA zone info.

Planting Calendar for Impatiens

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

Since impatiens require warm weather you must wait until after the last frost before you can plant them.

The earliest that you can plant impatiens in Sonoma 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 impatiens and expect a good harvest is probably September. You probably don't want to wait any later than that or else your impatiens may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your impatiens indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Sonoma. You should expect an average low temperature of 25°F in the coldest months of winter.

Remember that USDA zone info for Sonoma is an average and the actual date of last frost is different every year. Half of the time in Sonoma last frost occurs after February 15 so always be ready to cover your impatiens if you have a surprise late frost.

USDA Zone Info for Sonoma

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 Sonoma

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