The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 onions in Princeton by using the USDA zone info.

Planting Calendar for Onions

Frost tolerance for onions:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Onions tend to make it in pretty solid cold which means that you can plant them quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant onions in Princeton is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant onions and expect a good harvest is probably September. You probably don't want to wait any later than that or else your onions may not have a chance to fully mature. If you are starting your onions indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Princeton the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Princeton and it can change quite a bit from year to year. Half of the time in Princeton it frosts late in the year after April 15 so make sure that you are ready to protect your onions in the event of a late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Princeton

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