When to Plant Collard Greens in Illinois (2026 Guide)
When it comes to growing collard greens in Illinois, timing is essential. These hardy greens can thrive from spring until fall, with their flavor improving significantly after a frost. In many areas, including popular cities like Chicago and Aurora, you’ll want to pay close attention to your last spring frost date — for instance, April 26 in Zone 6a can be crucial for getting your collards started on time.
For gardeners in different zones across Illinois, understanding the local climate and adapting accordingly is key. In Zone 6b, for example, the median last frost date is April 13, allowing for even earlier planting. However, if you're in Zone 5b, you'll see your last frost occurring as late as May 3, making it essential to plan ahead, especially given the unique climate fluctuations that can happen in the state.
Collard greens are incredibly adaptable vegetables, capable of producing leafy greens for an extended season. With a growing period that might last as long as 186 days in certain areas like Belleville, you can continuously enjoy fresh collard greens throughout the months by harvesting selectively. This article outlines the best practices for getting the most from your collard greens in Illinois while addressing potential pitfalls in their cultivation.
Planting Schedule by USDA Zone in Illinois
| Zone | Indoor start | Transplant out | Direct sow | Harvest |
|---|---|---|---|---|
| Zone 6a | Start February 15 – March 1, ~6–8 weeks before April 26 | Transplant outdoors between April 27 – May 10 | Direct sow from April 27 – May 10 | Harvest from June 1 – November 1 |
| Zone 6b | Start February 15 – March 1, ~6–8 weeks before April 13 | Transplant outdoors between April 14 – April 30 | Direct sow from April 14 – April 30 | Harvest from May 15 – November 15 |
| Zone 5b | Start March 15 – March 30, ~6–8 weeks before May 3 | Transplant outdoors between May 4 – May 15 | Direct sow from May 4 – May 15 | Harvest from June 1 – October 15 |
Collard Greens Planting Windows in Illinois
- Indoor start: Start collard seeds indoors between February 15 and March 1 for optimal growth.
- Transplant outdoors: Transplant collard greens outdoors between April 14 and May 15, depending on your zone.
- Harvest: You can begin harvesting collard greens from June 1 and continue through November 15 for a bountiful supply.
Common Mistakes Growing Collard Greens in Illinois
- Many gardeners in Illinois don’t allow enough time for their collard greens to grow before frost sets in, leading to lost crops. Make sure to check local frost dates closely and schedule your planting accordingly.
- Improper watering is a common issue, especially during the hot summer month peaks. Illinois’ high humidity can sometimes mislead you regarding moisture levels in the soil, leading to under- or over-watering.
- Sometimes gardeners fail to account for the impact of late spring snows in Illinois, believing that it’s safe to plant too early. Make sure to observe local weather patterns and be ready to protect your young plants.
- An oversight when growing collards is planting them in southern or western rows where they may shade shorter companion plants. In Illinois, proper positioning is essential for optimizing your garden's productivity.
- Many Illinois gardeners do not rotate their collards away from other brassicas, which can lead to disease buildup in the soil. Effective crop rotation is crucial for maintaining healthy plants and soil in your garden.
Frequently Asked Questions
Can I plant collard greens if my garden is in a cold pocket of Illinois?
Yes, you can still plant collard greens in a cold pocket, but adjust your planting dates accordingly. Expect delays compared to warmer areas, so start indoors a bit earlier and wait until later for outdoor transplanting.
What if I missed the indoor starting window?
If you missed the indoor starting window, you can directly sow seeds outdoors within your zone's recommended dates. Just be aware that you may face a shorter growing season and smaller yields as a result.
Can I still plant collard greens in May?
Yes, you can plant collard greens in May, especially if you’re in Zone 6b. Just ensure that you check the local frost date and make any necessary adaptations. Late planting may also impact growth and yield.
How long does it take for collard greens to grow?
Collard greens typically take about 60 to 85 days from transplanting to reach a harvestable size. Your planting time in relation to frost dates will impact when you can start harvesting.
What conditions do collards prefer for optimal growth?
Collards thrive in full sun and well-drained, moisture-retentive soil. They appreciate consistent moisture, especially during hot summers in Illinois. Regular monitoring of soil conditions and pest populations is key to a successful harvest.
Keep Learning
City guides in Illinois
Other crops in Illinois
Typical fall sowing window for Collard Greens in Illinois: July 27 – August 17.