When can I plant Dahlias in Zone 9b

One of the first steps we take when we are estimating our gardening schedule is find our USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for our area.

The USDA zone info for Zone 9b should be used to estimate when you can plant dahlias.


Planting Calendar for Dahlias

Frost tolerance for dahlias: Not tolerant of frost.
When you should plant them: After the last frost.

It's not a good idea to plant dahlias until after the last frost because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant dahlias
Possibly ok, but a risky time to plant dahlias
Probably not a good time to plant dahlias

The earliest that you can plant dahlias in Zone 9b 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 really do well. 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 Zone 9b. We should expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that our actual date of last frost is not always accurate because it is based on the USDA zone info for Zone 9b and it will vary from year to year. Half of the time in Zone 9b we get a frost after February 15 so be sure to be ready to protect your dahlias in the event of a late frost.

USDA Zone Info for Zone 9b

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 Low25°F
Highest Expected Low30°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 Zone 9b

You may be interested in our other planting guides for Zone 9b.