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

In Marshalltown you can determine when it's a good idea to plant bishop's weed by checking out the USDA zone info.

Planting Calendar for Bishop's Weed

Frost tolerance for bishop's weed:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Bishop's Weed do well in cold weather which means that you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant bishop's weed in Marshalltown 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 bishop's weed and expect a good harvest is probably September. Any later than that and your bishop's weed may not have a chance to really do well. If you are starting your bishop's weed indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Marshalltown the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Marshalltown is an average the actual date of last frost is different every year. Half of the time in Marshalltown it frosts late in the year after April 15 so be sure to be ready to protect your bishop's weed in the event of a late frost.

USDA Zone Info for Marshalltown

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 Marshalltown

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