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Melvin/Projects/Hydroponic tower

An Arduino-controlled hydroponic tower, built at home during COVID

Strawberries grown without soil on a tower with 3D-printed pot holders. An Arduino monitored the water, ran the pump, the lights and the fan, and reported when the solution needed topping up.

Category
Hardware
Organization
Personal project, at home
Status
Delivered
Dates
2020
The tower running against a window: a vertical column with strawberry plants in printed pots up its height, lit either side by two LED grow bars.
The tower in the room where it ran, with an LED bar on each side. Strawberries, no soil, and water carrying the nutrients.

The tower

I built a hydroponic tower for strawberries at home in 2020, with the time COVID freed up. There is no soil. A pump lifts water from the reservoir at the base to the top of the column, and the roots take what they need as the water runs back down. An Arduino read the pH and the nutrient level, so I knew when to top up the solution and when to replace it. The same board ran the pump on a cycle it computed from the readings, instead of a fixed timer, and also controlled the grow lights and the ventilation.

The holder I printed

Nothing off the shelf held a pot the way this column needed. The part I modelled does two jobs. It clamps the net pot at the right angle, and it has a rail down one side where a stake slots in to hold up the strawberry branches, which sag once they carry fruit.

The pot holder, designed for two jobs

CAD render of the printed holder: a rounded shell with a round opening that takes the net pot, a small mounting hole on the face, and a straight rail with a square catch running down one side.
The opening holds the net pot at the angle the column needs. The rail down the side is the second job. A stake slots into it to hold up the branches.

The version that stayed on the tower

The printed holder held in one hand: white FDM plastic, visible print lines, the rail on the left side and two small drilled holes on the body.
Printed, tested on the column, adjusted, printed again. This is the one that stayed on.

A completed build

I finished the tower and ran it at home. It stayed in use until I moved out, when there was nobody left to refill the tank and check the water.