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.

The USDA zone info for Maryville can be reviewed to figure out when it's the best time 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.

You can plant tree onions just a tiny bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant tree onions in Maryville 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 tree onions and expect a good harvest is probably August. Any later than that and your tree onions may not have a chance to fully mature. If you are starting your tree onions indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Maryville the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Maryville and it changes from year to year. Half of the time in Maryville you get a frost after April 15 so make sure that you are prepared to cover your tree onions in the event of a surprise late frost.

USDA Zone Info for Maryville

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Maryville

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