Growing Kale Indoors — Complete Guide
Yes, Kale can be grown indoors. Here's everything you need to know: container size, light requirements, watering schedule, and how to avoid the most common mistakes.
Kale Indoors — At a Glance
Container Size for Indoor Kale
Recommended: 10–12 inch pot
Kale develops a substantial root system and grows large. Use a 10-inch pot minimum; a 12-inch pot produces a more productive plant. Compact varieties like 'Dwarf Blue Curled' suit containers best.
Light Requirements
Hours of Light Needed
14–16 hours
per day, consistently
Grow Light Recommendation
Full-spectrum LED grow light for 14–16 hours. Kale is productive under grow lights and tolerates lower light better than fruiting plants. 'Red Russian' kale grows well with less light than curly varieties.
Watering and Humidity
Ideal Humidity: 50–70%
Kale prefers cooler temperatures (60–70°F) and moderate humidity. It's cold-hardy and grows surprisingly well under grow lights in cool rooms. Avoid very warm, dry conditions.
Ideal Temperature: 55–75°F (13–24°C)
Keep away from cold drafts (air conditioning, windows in winter) and excessive heat sources (heaters, ovens). Consistent temperature produces the most vigorous growth.
How to Grow Kale Indoors: Step by Step
Choose a compact variety
Select 'Dwarf Blue Curled', 'Winterbor', or 'Red Russian' for indoor growing. These stay more manageable than large field varieties.
Sow or transplant
Sow seeds 1/2 inch deep in a 10–12 inch pot, 2–3 seeds. Thin to the strongest seedling. Or transplant a nursery seedling into fresh potting mix.
Provide strong light
Kale produces best under grow lights at 14–16 hours. Ensure the light source is close enough — 8–12 inches above the plant.
Water and feed regularly
Keep soil consistently moist. Feed with a nitrogen-rich liquid fertilizer every 2 weeks — kale is a heavy feeder and requires regular nutrition for continuous production.
Harvest outer leaves continuously
Always harvest outer, lower leaves first. Leave the central growing point intact. One plant can produce for 4–6 months with proper care.
Common Indoor Kale Problems & Fixes
Caterpillars or holes in leaves
Cause
Cabbage moth larvae — even indoors, moths can lay eggs on plants
Fix
Inspect leaves weekly, hand-pick caterpillars; use row cover fabric over plants
Yellowing lower leaves
Cause
Normal aging of lower leaves as plant grows upward
Fix
Remove yellowed leaves to maintain airflow; add liquid fertilizer every 2–3 weeks
Bitter taste
Cause
Heat or plant stress
Fix
Keep below 75°F; water consistently; harvest young leaves for best flavor
Frequently Asked Questions
Can I grow Kale indoors?
Yes, Kale can be grown indoors with the right conditions. You'll need 14–16 hours of Full sun or grow lights, a 10–12 inch pot, and temperatures of 55–75°F (13–24°C). The difficulty level for growing Kale indoors is Easy.
How much light does indoor Kale need?
Indoor Kale needs 14–16 hours of light per day. Full-spectrum LED grow light for 14–16 hours. Kale is productive under grow lights and tolerates lower light better than fruiting plants. 'Red Russian' kale grows well with less light than curly varieties.
What size container does indoor Kale need?
Kale develops a substantial root system and grows large. Use a 10-inch pot minimum; a 12-inch pot produces a more productive plant. Compact varieties like 'Dwarf Blue Curled' suit containers best.
Best Cities for Growing Kale Outdoors
If you're growing Kale indoors year-round, check the outdoor calendar for your city — you may be able to grow it outside during warmer months too.
Growing Kale Outdoors Too?
Find the best planting times for Kale in your city with our climate-based calendar.