One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Island Lake you should be able to estimate when to plant torenia.

Planting Calendar for Torenia

Frost tolerance for torenia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You should not plant torenia until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant torenia in Island Lake 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 torenia and expect a good harvest is probably August. If you wait any later than that and your torenia may not have a chance to grow to maturity. If you are starting your torenia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Island Lake. You can expect an average low temperature of -15°F in the coldest months of winter.

Remember that USDA zone info for Island Lake may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Island Lake you get surprised by a frost after April 15 be ready to protect your torenia if you have a late frost.

USDA Zone Info for Island Lake

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 Island Lake

You may be interested in your other planting guides for Island Lake.