One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of making a decision about when to plant tree onions is to use the USDA zone info for Waite Park.

Planting Calendar for Tree onions

Frost tolerance for tree onions:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since tree onions do ok in moderate cold you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant tree onions in Waite Park is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant tree onions and expect a good harvest is probably August. If you wait any later than that and your tree onions may not have a chance to really do well. You can get started a few weeks earlier by starting your tree onions indoors.

Last Frost Date

The average date of last frost is May 15 in Waite Park. In the coldest months of winter you can expect an average low temperature of -30°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Waite Park and it can change quite a bit from year to year. Since half of the time in Waite Park it frosts late in the year after May 15 be ready to cover your tree onions if you have one of those late frosts.

USDA Zone Info for Waite Park

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 Waite Park

You may be interested in your other planting guides for Waite Park.