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.

The best time to plant bishop's weed in Waterloo should be figured out by referring to 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.

Since bishop's weed are very cold tolerant you can plant them a lot earlier in the year than more sensitive plants.

The earliest that you can plant bishop's weed in Waterloo 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

On average the last frost when the weather gets warmer is on April 15 in Waterloo. It might get as low as -5°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Waterloo and it can change quite a bit from year to year. Half of the time in Waterloo last frost occurs after April 15 so always be ready to cover your bishop's weed in the event of a surprise late frost.

USDA Zone Info for Waterloo

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Waterloo

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