One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Princeton you should be able to estimate 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 Princeton 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 grow to maturity. 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

In Princeton the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Princeton may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Princeton you get a frost after April 15 so just be sure to be ready to protect your oxalis if you have a surprise late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Princeton

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