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.

The first chance to plant welsh onion in Washington can be determined by referring to the USDA zone info.

Planting Calendar for Welsh onion

Frost tolerance for welsh onion:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since welsh onion are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant welsh onion in Washington 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 welsh onion and expect a good harvest is probably August. Any later than that and your welsh onion may not have a chance to really do well. You can get started a few weeks earlier by starting your welsh onion indoors.

Last Frost Date

On average all chance of frost has passed is on March 15 in Washington. It might get as low as 10°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Washington and it is different every year. Half of the time in Washington you get surprised by a frost after March 15 so make sure that you are ready to protect your welsh onion if you have a late frost.

USDA Zone Info for Washington

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 Washington

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