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.

In Del Rio you can estimate when it's possible to plant dahlia by reviewing the USDA zone info.

Planting Calendar for Dahlia

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

Since dahlia require warm weather you need to wait until after the last frost has passed before you can plant them.

The earliest that you can plant dahlia in Del Rio 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. You can get started a couple of weeks earlier by starting your dahlia indoors.

Last Frost Date

The average date of last frost is February 15 in Del Rio. You should expect an average low temperature of 20°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Del Rio may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Del Rio it frosts late in the year after February 15 be ready to cover your dahlia in the event of a surprise late frost.

USDA Zone Info for Del Rio

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Del Rio

You may be interested in your other planting guides for Del Rio.