The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to figure out when to plant lysimachia by using the USDA zone info for Naperville.

Planting Calendar for Lysimachia

Frost tolerance for lysimachia:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Lysimachia are moderately cold tolerant which means that you can plant them earlier than other plants that might not handle the cold.

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

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

Last Frost Date

On average the last frost is on April 15 in Naperville. In the coldest months of winter you should expect an average low temperature of -15°F.

Remember that USDA zone info for Naperville is an average and the actual date of last frost will vary from year to year. Since half of the time in Naperville you get surprised by a frost after April 15 be ready to protect your lysimachia in the event of one of those late frosts.

USDA Zone Info for Naperville

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 Naperville

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