Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of determining when it's possible to plant tree onions is to look at the USDA zone info for Presque Isle.

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.

You can plant tree onions a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant tree onions in Presque Isle 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. You probably don't want to wait any later than that or else your tree onions may not have a chance to fully mature. Starting your tree onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Presque Isle. You should expect an average low temperature of -30°F in the coldest months of winter.

Keep in mind that USDA zone info for Presque Isle is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Presque Isle you get a frost after May 15 so be sure to be ready to protect your tree onions in the event of one of those late frosts.

USDA Zone Info for Presque Isle

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 Presque Isle

You may be interested in your other planting guides for Presque Isle.