One of the first steps you take when you are getting a good idea 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.

In Rochester you can estimate when to plant bidens by reviewing the USDA zone info.

Planting Calendar for Bidens

Frost tolerance for bidens:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since bidens are not cold tolerant it's necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant bidens in Rochester is May. However, you really should wait until June 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. You probably don't want to wait any later than that or else your bidens may not have a chance to grow to maturity. You can get started a little bit earlier by starting your bidens indoors.

Last Frost Date

On average the last frost is on May 15 in Rochester. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Rochester is just an average the actual date of last frost will vary from year to year. Half of the time in Rochester it frosts late in the year after May 15 so just be sure to be ready to cover your bidens in the event of one of those late frosts.

USDA Zone Info for Rochester

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Rochester

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