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.

The earliest that you can plant tree onions in Federal Way can be figured out by looking at 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.

Tree onions can survive in mild 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 Federal Way 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 really do well. Starting your tree onions indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Federal Way the average date of last frost happens on March 15. You can expect an average low temperature of 15°F in the coldest months of winter.

Keep in mind that USDA zone info for Federal Way is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Federal Way you get a frost after March 15 so make sure that you are prepared to cover your tree onions in the event of one of those late frosts.

USDA Zone Info for Federal Way

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 Federal Way

You may be interested in your other planting guides for Federal Way.