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 USDA zone info for Mercer Island can be looked at to determine when it's the best time to plant oxalis.

Planting Calendar for Oxalis

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

Since oxalis do not do well in cold weather it is important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant oxalis in Mercer Island 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. You probably don't want to wait any later than that or else your oxalis may not have a chance to fully mature. If you are starting your oxalis indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Mercer Island. In the coldest months of winter you can expect an average low temperature of 15°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Mercer Island and it will vary from year to year. Since half of the time in Mercer Island last frost occurs after March 15 be ready to cover your oxalis in the event of a late frost.

USDA Zone Info for Mercer Island

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 Mercer Island

You may be interested in your other planting guides for Mercer Island.