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.

By using the USDA zone info for Smithfield you will be able to estimate when to plant bidens.

Planting Calendar for Bidens

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

You should not plant bidens until after the last frost has passed because they require warm weather.

The earliest that you can plant bidens in Smithfield 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 grow to maturity. Starting your bidens indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Smithfield. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Smithfield may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Smithfield last frost occurs after April 15 be ready to protect your bidens if you have a surprise late frost.

USDA Zone Info for Smithfield

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 Smithfield

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