One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. 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 Hudson should be used to estimate when it's possible to plant tree onions.

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.

Tree onions are barely cold tolerant which means that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant tree onions in Hudson 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 really do well. If you are starting your tree onions indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Hudson. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Hudson may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Hudson there is a last frost after May 15 so just be sure to be ready to protect your tree onions in the event of a surprise late frost.

USDA Zone Info for Hudson

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 Hudson

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