One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Charles City you can estimate when it's a good idea to plant twinspur by using the USDA zone info.

Planting Calendar for Twinspur

Frost tolerance for twinspur:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Twinspur can survive in moderate cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant twinspur in Charles City is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant twinspur and expect a good harvest is probably September. Any later than that and your twinspur may not have a chance to fully mature. You can get started a few weeks earlier by starting your twinspur indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Charles City. It might get as low as -20°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Charles City is an average and the actual date of last frost is different every year. Half of the time in Charles City last frost occurs after April 15 so make sure that you are prepared to cover your twinspur if you have a surprise late frost.

USDA Zone Info for Charles City

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Charles City

You may be interested in your other planting guides for Charles City.