The USDA Zone info is a great tool for gardeners to help us estimate 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.

One way of estimating when to plant scallions is to look at the USDA zone info for Harvard.

Planting Calendar for Scallions

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

You can plant scallions slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant scallions in Harvard 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 scallions and expect a good harvest is probably August. You probably don't want to wait any later than that or else your scallions may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your scallions indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Harvard. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Harvard is an average the actual date of last frost changes from year to year. Since half of the time in Harvard last frost occurs after April 15 be ready to protect your scallions if you have a surprise late frost.

USDA Zone Info for Harvard

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 Harvard

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