When to Plant Rudbeckia in Denison, IA

One of the first steps you take when you are determining 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 first chance to plant rudbeckia in Denison can be determined by using 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.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant rudbeckia
Possibly ok, but a risky time to plant rudbeckia
Probably not a good time to plant rudbeckia

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

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

Last Frost Date

In Denison the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Denison is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Denison you get a frost after April 15 so just be sure to be ready to cover your rudbeckia in the event of a surprise late frost.

USDA Zone Info for Denison

Here is the info for USDA Zone 5a.

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

Plants to Grow in Denison

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