Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's the best time to plant tree onions by reviewing the USDA zone info for Sweet Home.

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 one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant tree onions in Sweet Home 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. 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

On average the last frost is on March 15 in Sweet Home. You can expect an average low temperature of 15°F in the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Sweet Home and it is different every year. Since half of the time in Sweet Home you get a frost after March 15 be ready to protect your tree onions if you have one of those late frosts.

USDA Zone Info for Sweet Home

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Sweet Home

You may be interested in your other planting guides for Sweet Home.