Before planting it is a good idea to find your USDA Zone info to figure out 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.

You can determine when it's possible to plant bittercress in Rock Island by looking at the USDA zone info.

Planting Calendar for Bittercress

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

Bittercress are one of those plants that can tolerate a tiny bit of cold weather which means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant bittercress in Rock Island 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 bittercress and expect a good harvest is probably August. If you wait any later than that and your bittercress may not have a chance to really do well. You can get started a couple of weeks earlier by starting your bittercress indoors.

Last Frost Date

The average date of last frost is April 15 in Rock Island. It might get as low as -15°F during the coldest months of winter.

Remember that USDA zone info for Rock Island is an average and the actual date of last frost will vary from year to year. Half of the time in Rock Island there is a last frost after April 15 so just be sure to be ready to protect your bittercress if you have a surprise late frost.

USDA Zone Info for Rock Island

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 Rock Island

You may be interested in your other planting guides for Rock Island.