The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to determine when it's a good idea to plant bidens by looking at the USDA zone info for Willows.

Planting Calendar for Bidens

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

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

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

The last month that you can plant bidens and expect a good harvest is probably September. Any later than that and your bidens may not have a chance to fully mature. If you are starting your bidens 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 February 15 in Willows. It might get as low as 25°F during the coldest months of winter.

It's important to remember that USDA zone info for Willows is not always accurate and the actual date of last frost is different every year. Half of the time in Willows there is a last frost after February 15 so make sure that you are ready to cover your bidens in the event of one of those late frosts.

USDA Zone Info for Willows

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in Willows

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