The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's a good idea to plant rudbeckia in Stillwater by checking out the USDA zone info.

Planting Calendar for Rudbeckia

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

Rudbeckia are moderately cold tolerant which means that you can get them planted earlier than more sensitive plants.

The earliest that you can plant rudbeckia 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 rudbeckia and expect a good harvest is probably August. If you wait any later than that and your rudbeckia may not have a chance to fully mature. You can get started a few weeks earlier by starting your rudbeckia indoors.

Last Frost Date

In Stillwater the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Keep in mind that USDA zone info for Stillwater may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Stillwater it frosts late in the year after May 15 be ready to cover your rudbeckia if you have one of those late frosts.

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.