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.

You will be able to determine when it's the best time to plant dahlia by referring to the USDA zone info for Williams.

Planting Calendar for Dahlia

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

You can not plant dahlia until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant dahlia in Williams 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. You probably don't want to wait any later than that or else your dahlia may not have a chance to really do well. Starting your dahlia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Williams is an average and the actual date of last frost changes from year to year. Half of the time in Williams you get a frost after February 15 so make sure that you are prepared to cover your dahlia in the event of one of those late frosts.

USDA Zone Info for Williams

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 Williams

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