The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Grass Valley should be read to estimate when it's the best time to plant dianthus.

Planting Calendar for Dianthus

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

Dianthus are moderately cold tolerant which tells us that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant dianthus in Grass Valley 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. You probably don't want to wait any later than that or else your dianthus may not have a chance to really do well. You can get started a few weeks earlier by starting your dianthus indoors.

Last Frost Date

The average date of last frost is February 15 in Grass Valley. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Grass Valley is just an average the actual date of last frost will vary from year to year. Since half of the time in Grass Valley you get surprised by a frost after February 15 be ready to cover your dianthus in the event of a surprise late frost.

USDA Zone Info for Grass Valley

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 Grass Valley

You may be interested in your other planting guides for Grass Valley.