Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of figuring out when it's possible to plant oxalis is to consult the USDA zone info for Waterloo.

Planting Calendar for Oxalis

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

Since oxalis are not cold tolerant it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant oxalis in Waterloo 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 really do well. If you are starting your oxalis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Waterloo. You can expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Waterloo is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Waterloo you get a frost after April 15 be ready to protect your oxalis if you have a surprise late frost.

USDA Zone Info for Waterloo

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Waterloo

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