One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to estimate when it's the best time to plant tree onions by looking at the USDA zone info for Mills River.

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 tend to make it in a tiny bit of cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant tree onions in Mills River 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 grow to maturity. 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 April 15 in Mills River. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Mills River is not always accurate the actual date of last frost changes from year to year. Half of the time in Mills River you get surprised by a frost after April 15 so be sure to be ready to cover your tree onions if you have a surprise late frost.

USDA Zone Info for Mills River

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Mills River

You may be interested in your other planting guides for Mills River.