When to Plant Geranium in Holmen, WI

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when it's possible to plant geranium is to refer to the USDA zone info for Holmen.


Planting Calendar for Geranium

Frost tolerance for geranium: Not tolerant of frost.
When to plant: After all chance of frost has passed.

Geranium are not cold tolerant which tells us that it's important to wait until it warms up after all chance of frost has passed before you can plant them.

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

The earliest that you can plant geranium in Holmen 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 geranium and expect a good harvest is probably August. Any later than that and your geranium may not have a chance to grow to maturity. Starting your geranium indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Holmen the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Holmen and it changes from year to year. Half of the time in Holmen last frost occurs after May 15 so always be ready to protect your geranium if you have a surprise late frost.

USDA Zone Info for Holmen

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 Holmen

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