One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

By referring to the USDA zone info for Harvard you should be able to figure out when it's possible to plant endive.

Planting Calendar for Endive

Frost tolerance for endive:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since endive are moderately cold tolerant you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant endive in Harvard 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 endive and expect a good harvest is probably September. If you wait any later than that and your endive may not have a chance to grow to maturity. If you are starting your endive indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is 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 may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Harvard it frosts late in the year after April 15 so be sure to be ready to protect your endive in the event of a 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.