One of the first steps you take when you are making a decision about 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.

By referring to the USDA zone info for Lisle you should be able to estimate when to plant geum.

Planting Calendar for Geum

Frost tolerance for geum:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since geum are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

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

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

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Lisle. 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 an average because it is based on the USDA zone info for Lisle and it is different every year. Since half of the time in Lisle last frost occurs after April 15 be ready to cover your geum if you have a surprise late frost.

USDA Zone Info for Lisle

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 Lisle

You may be interested in your other planting guides for Lisle.