š„¬When to Plant Kale in USDA Zone 5b (2026 Guide)
Frost actually sweetens it. Plant early spring and again for fall. Here is the cool-season planting schedule for kale in zone 5b (covering areas like Denver CO, Columbus OH). All dates are based on 2026 frost data for your zone.
Start Seeds Indoors
Mar 21
Direct sow or transplant
Apr 4
Harvest From
May 29
Because kale is a cool-season crop, it tolerates light frost and can go out around Apr 4, before zone 5b's average last frost on Apr 25.
- Type: Cool-season
- Method: Direct sow or transplant
- Days to harvest: 55
- Spacing: 12" apart
- Sun: Full sun to part shade
- Zone 5b frost: Apr 25 ā Oct 10
- Season length: ~168 days
- Companions: beets, onion, herbs
Growing kale in zone 5b
Zone 5b has an average last spring frost around Apr 25 and a first fall frost around Oct 10, giving roughly 168 frost-free growing days. That window comfortably fits kale's 55-day cycle, with room for a second succession planting if you time it right.
Get a head start by sowing seeds indoors around Mar 21, roughly 5 weeks before your last frost. Move the seedlings outside around Apr 4. Give each plant about 12 inches of space in full sun to part shade.
Zone 5b specific growing notes
In zone 5b (Denver CO, Columbus OH), your 168-day growing season means kale should be one of your first spring plantings. Cool-season crops thrive in the mild part of your growing window. Monitor soil temperature ā kale germinates best when soil is 40-75Ā°F.
Your first fall frost around Oct 10 means your last possible harvest is roughly late Oct. For a continuous supply, consider succession planting every 2-3 weeks from Apr 4 through mid-season.
Pro tip for kale
Frost converts starches to sugarākale harvested after a light freeze tastes noticeably sweeter. Harvest the oldest outer leaves first and the plant keeps producing from the center for months.
Troubleshooting kale
Cabbage aphids cluster in dense gray colonies inside leaf crevices and growing tips. A strong jet of water knocks most off. For persistent infestations, insecticidal soap or neem oil applied to leaf undersides works well.
Growing kale in containers
One plant per 3-gallon pot minimum. Kale is ornamental enough for mixed flower plantersāvarieties like 'Red Russian' and 'Lacinato' (dinosaur kale) look striking alongside annual flowers.
Can you plant kale twice a year?
Yesāspring and fall crops are standard practice. In zones 5+, start fall kale indoors in early July and transplant by early August. Mature kale survives winter down to zone 5 with minimal protection.
Frequently asked questions
When should I plant kale in zone 5b?
Direct sow or transplant around Apr 4. If starting from seed indoors, sow around Mar 21. Because kale is a cool-season crop, it tolerates light frost and can go out around Apr 4, before zone 5b's average last frost on Apr 25.
How long does kale take to grow in zone 5b?
About 55 days from sowing to first harvest. A Apr 4 planting in zone 5b is typically ready to pick from around May 29. Zone 5b has about 168 frost-free days ā plenty of time for a second succession planting.
How far apart should I space kale?
Space kale about 12 inches apart in full sun to part shade. This gives each plant enough room for roots to spread and leaves to catch sunlight without competing.
What is the best tip for growing kale?
Frost converts starches to sugarākale harvested after a light freeze tastes noticeably sweeter. Harvest the oldest outer leaves first and the plant keeps producing from the center for months.
What are common problems with kale and how do I fix them?
Cabbage aphids cluster in dense gray colonies inside leaf crevices and growing tips. A strong jet of water knocks most off. For persistent infestations, insecticidal soap or neem oil applied to leaf undersides works well.
Can I grow kale in a container?
One plant per 3-gallon pot minimum. Kale is ornamental enough for mixed flower plantersāvarieties like 'Red Russian' and 'Lacinato' (dinosaur kale) look striking alongside annual flowers.
Can I plant a second crop of kale for fall harvest?
Yesāspring and fall crops are standard practice. In zones 5+, start fall kale indoors in early July and transplant by early August. Mature kale survives winter down to zone 5 with minimal protection.
What grows well next to kale?
Good companion plants for kale are beets, onion, herbs. Avoid planting near warm-season crops that compete for space and nutrients. Kale also benefits from crop rotation ā do not plant it in the same spot year after year.