One of the first steps you take when you are estimating 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.

In Stillwater you can determine when to plant dianthus by checking out 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.

Since dianthus are moderately cold tolerant you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant dianthus in Stillwater 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 dianthus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your dianthus may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your dianthus indoors.

Last Frost Date

The average date of last frost is May 15 in Stillwater. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Stillwater is just an average the actual date of last frost is different every year. Since half of the time in Stillwater it frosts late in the year after May 15 be ready to cover your dianthus in the event of a surprise late frost.

USDA Zone Info for Stillwater

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Stillwater

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