The USDA Zone info is a great tool for gardeners to help us determine 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.

By reviewing the USDA zone info for Merrill you should be able to estimate when it's the best time to plant rudbeckia.

Planting Calendar for Rudbeckia

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

Rudbeckia do ok in a little bit of cold which tells us that you can plant them a bit earlier in the year than more sensitive plants.

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

Last Frost Date

On average all chance of frost has passed is on May 15 in Merrill. You can expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Merrill is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Merrill there is a last frost after May 15 be ready to protect your rudbeckia if you have a surprise late frost.

USDA Zone Info for Merrill

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Merrill

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