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 USDA zone info for Silvis should be read to determine when it's a good idea to plant browallia.

Planting Calendar for Browallia

Frost tolerance for browallia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since browallia do not do well in cold weather you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant browallia in Silvis is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant browallia and expect a good harvest is probably August. If you wait any later than that and your browallia may not have a chance to grow to maturity. Starting your browallia indoors is a great way to get them started a couple of 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.

Since the USDA zone info for Silvis may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Silvis you get surprised by a frost after April 15 so make sure that you are prepared to protect your browallia 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.