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 USDA zone info for Onalaska should be reviewed to estimate when it's a good idea to plant spinach.

Planting Calendar for Spinach

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

Spinach are one of those plants that can tolerate a little bit of cold weather which tells us that you can start planting them earlier than other frost tender plants.

The earliest that you can plant spinach in Onalaska 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 spinach and expect a good harvest is probably August. Any later than that and your spinach may not have a chance to really do well. Starting your spinach indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Onalaska is not always accurate the actual date of last frost will vary from year to year. Half of the time in Onalaska last frost occurs after May 15 so make sure that you are ready to protect your spinach if you have a surprise late frost.

USDA Zone Info for Onalaska

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 Onalaska

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