One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when to plant pearl onions is to use the USDA zone info for Boonton.

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 do ok in moderate cold which tells us that you can plant them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant pearl onions in Boonton 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 grow to maturity. If you are starting your pearl onions indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Boonton. You should expect an average low temperature of -5°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Boonton and it can change quite a bit from year to year. Half of the time in Boonton there is a last frost after April 15 so always be ready to cover your pearl onions in the event of a surprise late frost.

USDA Zone Info for Boonton

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 Boonton

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