One of the first steps you take when you are getting a good idea 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.

You can figure out when it's a good idea to plant oxalis in Lake Oswego 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 when the weather gets warmer.

Oxalis do not do well in cold weather which means that you need to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant oxalis in Lake Oswego 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 couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Lake Oswego. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Lake Oswego is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Lake Oswego you get surprised by a frost after March 15 be ready to protect your oxalis if you have a late frost.

USDA Zone Info for Lake Oswego

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 Lake Oswego

You may be interested in your other planting guides for Lake Oswego.