One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of getting a good idea when it's a good idea to plant leeks is to refer to the USDA zone info for Princeton.

Planting Calendar for Leeks

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

Leeks do well in cold which tells us that you can plant them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant leeks 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 leeks and expect a good harvest is probably August. Any later than that and your leeks may not have a chance to grow to maturity. Starting your leeks indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Princeton the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -30°F.

Remember that the actual date of last frost is just an average 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 May 15 so always be ready to protect your leeks in the event of one of those late frosts.

USDA Zone Info for Princeton

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Princeton

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