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.

By reviewing the USDA zone info for Harvard you should be able to figure out when you can plant bidens.

Planting Calendar for Bidens

Frost tolerance for bidens:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant bidens until after the last frost because they do not do well in cold weather.

The earliest that you can plant bidens in Harvard is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant bidens and expect a good harvest is probably August. Any later than that and your bidens may not have a chance to grow to maturity. Starting your bidens indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Harvard. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Harvard is an average the actual date of last frost will vary from year to year. Since half of the time in Harvard it frosts late in the year after April 15 be ready to cover your bidens if you have one of those late frosts.

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.