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.

By referring to the USDA zone info for Birmingham it's a good idea 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.

Bidens require warm weather which tells us that you have to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant bidens in Birmingham 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. You can get started a little bit earlier by starting your bidens indoors.

Last Frost Date

On average the last frost is on March 15 in Birmingham. It might get as low as 10°F during the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Birmingham and it is different every year. Half of the time in Birmingham you get surprised by a frost after March 15 so be sure to be ready to cover your bidens if you have a surprise late frost.

USDA Zone Info for Birmingham

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Birmingham

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