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.

It's a good idea to determine when it's the best time to plant pearl onions by referring to the USDA zone info for Princeton.

Planting Calendar for Pearl onions

Frost tolerance for pearl onions:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Pearl onions are barely cold tolerant which tells us that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

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

The last month that you can plant pearl onions and expect a good harvest is probably August. Any later than that and your pearl onions may not have a chance to fully mature. You can get started a few weeks earlier by starting your pearl onions indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Princeton. In the coldest months of winter you can expect an average low temperature of -15°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Princeton and it can change quite a bit from year to year. Since half of the time in Princeton there is a last frost after April 15 be ready to cover your pearl onions in the event of one of those late frosts.

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.