Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Warrenton you can determine when to plant dahlia 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.

It's probably a bad idea to plant dahlia until after the last frost because they do not do well in cold weather.

The earliest that you can plant dahlia in Warrenton 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. Any later than that and your dahlia may not have a chance to fully mature. Starting your dahlia indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on February 15 in Warrenton. It might get as low as 20°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Warrenton and it can change quite a bit from year to year. Since half of the time in Warrenton there is a last frost after February 15 be ready to cover your dahlia if you have a surprise late frost.

USDA Zone Info for Warrenton

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 Warrenton

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