Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of figuring out when you can plant bidens is to consult the USDA zone info for Snoqualmie.

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 you must wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant bidens in Snoqualmie 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 fully mature. You can get started a couple of weeks earlier by starting your bidens indoors.

Last Frost Date

The average date of last frost is March 15 in Snoqualmie. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Snoqualmie is an average the actual date of last frost changes from year to year. Half of the time in Snoqualmie you get surprised by a frost after March 15 so be sure to be ready to cover your bidens if you have one of those late frosts.

USDA Zone Info for Snoqualmie

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Snoqualmie

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