One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Zone 10b you can determine when it's the best time to plant dahlias by referring to the USDA zone info.

Planting Calendar for Dahlias

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

Dahlias require warm weather which means that it's necessary to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant dahlias in Zone 10b is February. However, you really should wait until March 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. You probably don't want to wait any later than that or else your dahlias may not have a chance to fully mature. If you are starting your dahlias indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in Zone 10b. It might get as low as 35°F during the coldest months of winter.

Always keep in mind that USDA zone info for Zone 10b may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Zone 10b last frost occurs after January 31 so make sure that you are ready to protect your dahlias if you have one of those late frosts.

USDA Zone Info for Zone 10b

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in Zone 10b

You may be interested in your other planting guides for Zone 10b.