Wick hydroponics: the simplest passive system
A wick draws nutrient solution into an absorbent growing medium. It has no pump and suits small herbs, but it cannot move enough water for thirsty, fruiting crops.
The short version
A wick draws nutrient solution into an absorbent growing medium. It has no pump and suits small herbs, but it cannot move enough water for thirsty, fruiting crops. The useful test is not whether a method can work, but whether it keeps the roots supplied with water, dissolved nutrients and oxygen while the leaves receive enough light.
- Synthetic cord often wicks more consistently than untreated natural fibre.
- The medium must stay aerated as well as moist.
- Salt can collect where water evaporates.
A practical way to do it
- 1
Pre-wet the wick and medium.
Make this change deliberately, then observe the plant and system before changing the next variable. That separation makes the result useful.
- 2
Run at least one wick into the reservoir.
Make this change deliberately, then observe the plant and system before changing the next variable. That separation makes the result useful.
- 3
Keep the pot above the waterline.
Make this change deliberately, then observe the plant and system before changing the next variable. That separation makes the result useful.
- 4
Flush or replace crusted medium.
Make this change deliberately, then observe the plant and system before changing the next variable. That separation makes the result useful.
What to watch
Look at the whole system before diagnosing a single leaf. Check new and old growth separately, lift the lid to inspect root colour and texture, confirm that water or air is moving, and compare today’s readings with the last entry in your log.
Adding more concentrated feed does not compensate for a wick that cannot supply enough water.
Make the setup easier to live with
Put inspection points where you can reach them without moving plants. Label cables, nutrient bottles and measuring tools. A waterproof tray, a marked full-water line and a simple notebook prevent more trouble than an elaborate controller. When a crop finishes, remove roots promptly and clean the parts you can now reach.
Questions people ask
What is the simplest way to act on this guide?
Pre-wet the wick and medium.
What is the most common mistake?
Adding more concentrated feed does not compensate for a wick that cannot supply enough water.
What should I record?
Write down dates, water volume, nutrient dose, pH and EC readings where relevant, plus one photograph. A short record makes patterns much easier to diagnose.
Sources
Checked 10 November 2026. Product labels and local conditions take precedence.
- Hydroponics gardening — Royal Horticultural Society
- Hydroponics — Oklahoma State University Extension
- Work using electrically powered equipment — Health and Safety Executive