One of the first steps you take when you are figuring out 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 best time to plant oxalis in Washington can be determined by referring to the USDA zone info.

Planting Calendar for Oxalis

Frost tolerance for oxalis:	Not tolerant of frost.
When to plant:	After the last frost.

Oxalis require warm weather which tells us that you have to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant oxalis in Washington is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant oxalis and expect a good harvest is probably August. If you wait any later than that and your oxalis may not have a chance to really do well. Starting your oxalis indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Washington. It might get as low as 10°F during the coldest months of winter.

It's important to remember that USDA zone info for Washington is not always accurate and the actual date of last frost 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 prepared to cover your oxalis in the event of one of those late frosts.

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.