Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Tucson you can estimate when it's a good idea to plant dianthus by referring to the USDA zone info.

Planting Calendar for Dianthus

Frost tolerance for dianthus:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Dianthus do well in moderate cold which means that you can start planting them earlier than other frost tender plants.

The earliest that you can plant dianthus in Tucson is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant dianthus and expect a good harvest is probably October. Any later than that and your dianthus may not have a chance to fully mature. Starting your dianthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Tucson. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Tucson may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Tucson it frosts late in the year after February 15 so make sure that you are prepared to protect your dianthus in the event of a late frost.

USDA Zone Info for Tucson

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 Tucson

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