Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Silvis should be reviewed to figure out when it's possible to plant bishop's weed.

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.

You can plant bishop's weed much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant bishop's weed in Silvis 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. If you wait any later than that and your bishop's weed may not have a chance to really do well. You can get started a little bit earlier by starting your bishop's weed indoors.

Last Frost Date

In Silvis the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Silvis is just an average the actual date of last frost will vary from year to year. Half of the time in Silvis it frosts late in the year after April 15 so make sure that you are ready to cover your bishop's weed if you have a surprise late frost.

USDA Zone Info for Silvis

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 Silvis

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