One of the first steps you take when you are figuring out 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.

By referring to the USDA zone info for Terre Haute you should be able to determine when it's a good idea to plant bidens.

Planting Calendar for Bidens

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

You really shouldn't plant bidens until after the last frost because they require warm weather.

The earliest that you can plant bidens in Terre Haute 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. You probably don't want to wait any later than that or else your bidens may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your bidens indoors.

Last Frost Date

In Terre Haute the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Terre Haute is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Terre Haute you get surprised by a frost after April 15 be ready to protect your bidens in the event of a late frost.

USDA Zone Info for Terre Haute

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Terre Haute

You may be interested in your other planting guides for Terre Haute.