One of the first steps you take when you are figuring out your gardening schedule is find your 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.

The earliest that you can plant bunching onions in Rock Island should be estimated by using the USDA zone info.

Planting Calendar for Bunching Onions

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

You can plant bunching onions a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant bunching onions 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 bunching onions and expect a good harvest is probably August. If you wait any later than that and your bunching onions may not have a chance to really do well. You can get started a little bit earlier by starting your bunching onions indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Rock Island. In the coldest months of winter you should expect an average low temperature of -15°F.

Just be sure to remember that USDA zone info for Rock Island is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Rock Island it frosts late in the year after April 15 so be sure to be ready to protect your bunching onions in the event of 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.