When to Plant Dahlias in Pittsburg, CA

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of getting a good idea when it's possible to plant dahlias is to refer to the USDA zone info for Pittsburg.


Planting Calendar for Dahlias

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

Dahlias are not cold tolerant which means that it is important to wait until it warms up after the last frost has passed 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 Pittsburg 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 fully mature. Starting your dahlias indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Just be sure to remember 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 Pittsburg and it changes from year to year. Half of the time in Pittsburg it frosts late in the year after February 15 so just be sure to be ready to protect your dahlias in the event of a late frost.

USDA Zone Info for Pittsburg

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 Pittsburg

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