When to Plant Dahlias in Larkspur, CA

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to estimate when you can plant dahlias by checking out the USDA zone info for Larkspur.


Planting Calendar for Dahlias

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

Since dahlias are not cold tolerant it's necessary to wait until after the last frost when the weather gets warmer before you can plant them.

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 Larkspur 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. You probably don't want to wait any later than that or else your dahlias may not have a chance to grow to maturity. You can get started a little bit earlier by starting your dahlias indoors.

Last Frost Date

In Larkspur the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Larkspur and it can change quite a bit from year to year. Since half of the time in Larkspur it frosts late in the year after February 15 be ready to protect your dahlias if you have a surprise late frost.

USDA Zone Info for Larkspur

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 Larkspur

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