The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Lisle should be reffered to in order to determine when you can plant platycodon.

Planting Calendar for Platycodon

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

Platycodon are barely cold tolerant which means that you can start planting them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant platycodon 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 platycodon and expect a good harvest is probably August. Any later than that and your platycodon may not have a chance to really do well. If you are starting your platycodon indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Lisle. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Lisle is just an average the actual date of last frost is different every year. Half of the time in Lisle last frost occurs after April 15 so make sure that you are ready to protect your platycodon in the event of one of those late frosts.

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.