When to Plant Dahlias in Union City, CA

One of the best tools that you have as gardeners to help us figure out 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.

The USDA zone info for Union City should be reviewed to estimate when it's possible to plant dahlias.


Planting Calendar for Dahlias

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

Dahlias do not do well in cold weather which tells us that it is necessary to wait until it warms up 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 Union City 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. Starting your dahlias indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Union City the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Always keep in mind that USDA zone info for Union City is just an average and the actual date of last frost changes from year to year. Half of the time in Union City there is a last frost after January 31 so just be sure to be ready to cover your dahlias if you have one of those late frosts.

USDA Zone Info for Union City

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)January 31
Average Date of First Frost (fall)December 15
Lowest Expected Low30°F
Highest Expected Low35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Union City

You may be interested in your other planting guides for Union City.