One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Joshua should be used to estimate when it's a good idea to plant dahlias.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After the last frost.

Since dahlias do not do well in cold weather you must wait until after the last frost before you can plant them.

The earliest that you can plant dahlias in Joshua is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant dahlias and expect a good harvest is probably August. If you wait any later than that and your dahlias may not have a chance to really do well. You can get started a couple of weeks earlier by starting your dahlias indoors.

Last Frost Date

In Joshua the average date of last frost happens on March 15. You should expect an average low temperature of 10°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Joshua and it is different every year. Half of the time in Joshua last frost occurs after March 15 so always be ready to protect your dahlias in the event of one of those late frosts.

USDA Zone Info for Joshua

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Joshua

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