When to Plant Hypericum in River Grove, IL

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's possible to figure out when it's the best time to plant hypericum by checking out the USDA zone info for River Grove.


Planting Calendar for Hypericum

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

Hypericum do well in some cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant hypericum
Possibly ok, but a risky time to plant hypericum
Probably not a good time to plant hypericum

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

Last Frost Date

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

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for River Grove and it is different every year. Half of the time in River Grove you get surprised by a frost after April 15 so make sure that you are ready to protect your hypericum in the event of a surprise late frost.

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.