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.

The earliest that you can plant nasturtium in Rock Falls can be determined by using the USDA zone info.

Planting Calendar for Nasturtium

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

You really shouldn't plant nasturtium until after the last frost when the weather gets warmer because they are not cold tolerant.

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

Last Frost Date

In Rock Falls the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Rock Falls and it can change quite a bit from year to year. Since half of the time in Rock Falls you get a frost after April 15 be ready to protect your nasturtium in the event of a surprise late frost.

USDA Zone Info for Rock Falls

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 Falls

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