The USDA Zone info is a great tool for gardeners to help us figure out 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 Napa can be read to estimate when to plant achimenes.

Planting Calendar for Achimenes

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

Achimenes are not cold tolerant which tells us that you really should wait until it warms up after the last frost before you can plant them.

The earliest that you can plant achimenes in Napa 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 achimenes and expect a good harvest is probably September. You probably don't want to wait any later than that or else your achimenes may not have a chance to fully mature. Starting your achimenes indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Napa and it changes from year to year. Since half of the time in Napa you get a frost after February 15 be ready to protect your achimenes if you have a late frost.

USDA Zone Info for Napa

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 Napa

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