One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

By referring to the USDA zone info for River Grove you will be able to determine when it's a good idea to plant asters.

Planting Calendar for Asters

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

You can plant asters a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant asters in River Grove 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 asters and expect a good harvest is probably September. Any later than that and your asters may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your asters indoors.

Last Frost Date

On average the last frost has passed is on April 15 in River Grove. You can expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for River Grove is an average and the actual date of last frost will vary from year to year. Since half of the time in River Grove it frosts late in the year after April 15 be ready to cover your asters if you have one of those late frosts.

USDA Zone Info for River Grove

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 River Grove

You may be interested in your other planting guides for River Grove.