Most problems with Kratky tomatoes come back to a handful of causes: the water level, the pH, the nutrient strength, the light or the temperature. Find your symptom below, then work through the check order before changing anything.
Find Your Symptom
| What you see | Most likely causes | Guide |
|---|---|---|
| Dark, sunken patch on the bottom of the fruit | Calcium not reaching the fruit, often from an uneven water supply | Blossom end rot |
| Leaves turning yellow | pH out of range, low nutrients, root trouble or low light | Yellow tomato leaves |
| Flowers open, then drop with no fruit | No pollination indoors, heat or cold, low light | Tomato flowers falling off |
| Plant wilts while standing in water; brown, slimy roots | Air roots drowned, warm solution, low oxygen | Root rot in Kratky |
| Green slime or film in the container | Light reaching the solution | Algae in a Kratky reservoir |
Check in This Order
Most fixes are cheap, so check the simple things first:
- Water level. Is there an air gap? Are the water roots still in the solution? See topping up a Kratky tomato reservoir.
- pH. Is it between 5.5 and 6.5? See Kratky tomato pH.
- Nutrient strength. Is the EC right for the plant's stage? See Kratky tomato nutrients.
- Roots. Are they white and firm, or brown and slimy?
- Light and temperature. Is the plant getting enough light, and is it too hot or cold? See grow lights for indoor tomatoes.
Change one thing at a time and give the plant a few days before changing the next.
Back to the Kratky method for tomatoes.
Frequently Asked Questions
What is the most common Kratky tomato problem?
Problems with the water level: either the container runs low as the tomato drinks, or it is refilled too high and drowns the air roots. Both are fixed by topping up only to the water roots.
Why is my Kratky tomato wilting when it has water?
Usually because its roots are damaged and can't take water up, most often from root rot after the air roots were submerged or the solution got too warm.