The USDA Zone info is a great tool for gardeners to help us determine your gardening 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 looked at to estimate when it's a good idea to plant heuchera.

Planting Calendar for Heuchera

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

Since heuchera do well in moderate cold you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant heuchera 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 heuchera and expect a good harvest is probably September. Any later than that and your heuchera may not have a chance to grow to maturity. If you are starting your heuchera indoors then you might be able to get away with starting them a few weeks earlier.

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.

Remember that USDA zone info for Silvis is an average and the actual date of last frost changes from year to year. Since half of the time in Silvis it frosts late in the year after April 15 be ready to cover your heuchera 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.