One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to estimate when to plant streptocarpella by checking out the USDA zone info for Rock Island.

Planting Calendar for Streptocarpella

Frost tolerance for streptocarpella:	Not tolerant of frost.
When to plant:	After the last frost.

You really shouldn't plant streptocarpella until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant streptocarpella in Rock Island 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 streptocarpella and expect a good harvest is probably August. You probably don't want to wait any later than that or else your streptocarpella may not have a chance to really do well. Starting your streptocarpella indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Rock Island. You should expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that USDA zone info for Rock Island is just an average and the actual date of last frost is different every year. Half of the time in Rock Island you get a frost after April 15 so make sure that you are ready to cover your streptocarpella if you have a surprise late frost.

USDA Zone Info for Rock Island

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 Rock Island

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