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.

By using the USDA zone info for Patterson you should be able to determine when it's possible to plant dahlia.

Planting Calendar for Dahlia

Frost tolerance for dahlia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Dahlia are not cold tolerant which means that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant dahlia in Patterson 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 dahlia and expect a good harvest is probably September. Any later than that and your dahlia may not have a chance to really do well. You can get started a little bit earlier by starting your dahlia indoors.

Last Frost Date

The average date of last frost is February 15 in Patterson. 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 Patterson is an average and the actual date of last frost is different every year. Since half of the time in Patterson you get a frost after February 15 be ready to cover your dahlia in the event of a surprise late frost.

USDA Zone Info for Patterson

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 Patterson

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