The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when to plant dahlia in Vallejo by looking at the USDA zone info.

Planting Calendar for Dahlia

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

Dahlia are not cold tolerant which tells us that you must wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dahlia in Vallejo 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 dahlia and expect a good harvest is probably September. If you wait any later than that and your dahlia may not have a chance to really do well. If you are starting your dahlia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Vallejo the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Vallejo and it will vary from year to year. Half of the time in Vallejo you get surprised by a frost after February 15 so be sure to be ready to protect your dahlia in the event of one of those late frosts.

USDA Zone Info for Vallejo

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 Low	25°F
Highest Expected Low	30°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 Vallejo

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