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 best time to plant dahlias in Oroville should be estimated by checking out the USDA zone info.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After the last frost.

Since dahlias do not do well in cold weather you must wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlias in Oroville 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 dahlias and expect a good harvest is probably September. Any later than that and your dahlias may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your dahlias indoors.

Last Frost Date

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

Since the USDA zone info for Oroville is an average the actual date of last frost will vary from year to year. Half of the time in Oroville it frosts late in the year after February 15 so be sure to be ready to cover your dahlias if you have a surprise late frost.

USDA Zone Info for Oroville

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 Oroville

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