Before planting it is a good idea to find your USDA Zone info to determine 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.

The first chance to plant tree onions in Marion should be estimated by using the USDA zone info.

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 just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant tree onions in Marion 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. You probably don't want to wait any later than that or else 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 little bit earlier.

Last Frost Date

In Marion the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for Marion is not always accurate the actual date of last frost changes from year to year. Since half of the time in Marion it frosts late in the year after March 15 be ready to cover your tree onions if you have a late frost.

USDA Zone Info for Marion

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Marion

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