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.

You can determine when to plant oxalis in Zone 3a 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 require warm weather which means that you need to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant oxalis in Zone 3a is May. However, you really should wait until June 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 grow to maturity. Starting your oxalis indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Zone 3a the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -40°F.

Keep in mind that USDA zone info for Zone 3a is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 3a last frost occurs after May 15 so just be sure to be ready to cover your oxalis if you have a late frost.

USDA Zone Info for Zone 3a

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-40°F
Highest Expected Low	-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in Zone 3a

You may be interested in your other planting guides for Zone 3a.