When to Plant Zinnia in New Ulm, MN

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 best time to plant zinnia in New Ulm should be figured out by reviewing the USDA zone info.


Planting Calendar for Zinnia

Frost tolerance for zinnia: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

Since zinnia require warm weather it is necessary to wait until after the last frost has passed before you can plant them.

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

The earliest that you can plant zinnia in New Ulm is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant zinnia and expect a good harvest is probably August. If you wait any later than that and your zinnia may not have a chance to fully mature. Starting your zinnia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for New Ulm is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in New Ulm you get surprised by a frost after May 15 be ready to cover your zinnia if you have one of those late frosts.

USDA Zone Info for New Ulm

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 New Ulm

You may be interested in your other planting guides for New Ulm.