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

The USDA zone info for Holmen can be read to estimate when it's the best time to plant oxalis.

Planting Calendar for Oxalis

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

Since oxalis are not cold tolerant you need to wait until after the last frost has passed before you can plant them.

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

Last Frost Date

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

Just be sure to remember that USDA zone info for Holmen is an average and the actual date of last frost changes from year to year. Half of the time in Holmen you get a frost after May 15 so make sure that you are prepared to protect your oxalis in the event of one of those late frosts.

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.