Kratky Method 2026: Complete Passive Hydroponics Guide
Master the Kratky method for passive hydroponics. No pumps, no electricity. Perfect for beginners growing lettuce, herbs, and greens.
Obsessive researcher who reads every Reddit thread and expert review so you don't have to. Years of research behind every guide.
Not sure which setup is right for you?
Take Our QuizThe Kratky method is hydroponics stripped to its absolute essentials. No pumps. No electricity. No complexity. Just plants growing in nutrient water. It's named after B.A. Kratky, the University of Hawaii researcher who formalized the technique.
## Quick Picks: Kratky Supplies
| Item | Recommended | Price | Notes |
|---|---|---|---|
| Containers | Mason jars or storage bins | $5-15 | Must block light |
| Net pots | 50-pack 2-inch | Around $13 | Standard size for herbs |
| Growing medium | Clay pebbles | Around $20 | Reusable indefinitely |
| Nutrients | General Hydroponics Flora | Around $40 | Three-part, flexible |
| pH kit | Drops or digital | $10-25 | Essential |
The honest truth: Kratky is the cheapest way to learn hydroponics. A complete setup costs under $35. Success teaches you principles that apply to every other system.
## How It Actually Works
Fill a container with nutrient solution. Suspend a plant in a net pot so roots reach the water. Leave an air gap between the water surface and the net pot. This is the crucial detail.
As the plant drinks and grows, the water level drops. Roots that were submerged become exposed to air for oxygen. New roots grow downward to follow the receding water. The plant essentially regulates itself.
This is why you don't top up the water mid-grow. Maintaining the air gap is more important than maintaining water level. The exposed roots are breathing.
## Setting Up Step by Step
1. Prepare your container: Clean thoroughly. If transparent, wrap in foil or cover to block light. 2. Cut or fit net pot holes: The net pot should sit snugly with most of its depth above the lid and about half an inch below. 3. Mix nutrient solution: Fill container with water, add nutrients at half strength, adjust pH to 5.5-6.5. 4. Add growing medium: Fill net pot with rinsed clay pebbles or similar inert medium. 5. Position seedling: Place seedling so roots touch or nearly touch the water surface. 6. Create air gap: Water level should be about half an inch below the bottom of the net pot initially. 7. Place under light: Sunny window or grow light. Herbs need 12-16 hours of light daily. 8. Wait: Seriously. The main intervention is waiting.
Total cost: Around $20-30. Time to first harvest: 4-6 weeks.
## Best Kratky Crops
Excellent: Lettuce (all varieties), basil, mint, cilantro, spinach, arugula, kale, Swiss chard
Possible (need larger containers): Cherry tomatoes, peppers, strawberries, beans
Difficult (not recommended for beginners): Large tomatoes, cucumbers, root vegetables
## Our Take
Kratky is the best way to learn hydroponics. Period. Start with lettuce in a storage bin or basil in a mason jar. If it works, you've learned the fundamentals for under $35.
If you're just getting started, our indoor herb garden guide is the perfect companion. And when you're ready for pH management (you will be), the pH guide is essential reading.
Take our quiz if you want recommendations for your specific space and growing goals.
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