One of the first steps you take when you are getting a good idea 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 Firestone should be reviewed to estimate when it's a good idea 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 do ok in moderate cold which tells us that you can start planting them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant tree onions in Firestone 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. If you wait any later than that and your tree onions may not have a chance to fully mature. You can get started a few weeks earlier by starting your tree onions indoors.

Last Frost Date

On average the last frost is on April 15 in Firestone. In the coldest months of winter you should expect an average low temperature of -15°F.

Always keep in mind that USDA zone info for Firestone may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Firestone last frost occurs after April 15 so always be ready to cover your tree onions if you have a late frost.

USDA Zone Info for Firestone

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 Firestone

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