One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant bidens in Westminster should be estimated by referring to the USDA zone info.

Planting Calendar for Bidens

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

It's probably not a good idea to plant bidens until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant bidens in Westminster 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. If you wait any later than that and your bidens may not have a chance to grow to maturity. Starting your bidens indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Westminster is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Westminster last frost occurs after April 15 so make sure that you are ready to cover your bidens if you have a late frost.

USDA Zone Info for Westminster

Here is the info for USDA Zone 5b.

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

Plants to Grow in Westminster

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