A nursery in 80x37 cm: how I built it
A closed cabinet, four LED bars and a timer. How I turned a living-room unit into a home nursery for 15+ mother plants, and what I would do differently.
The nursery is a living-room display cabinet, eighty centimetres wide by thirty-seven deep. It is not a greenhouse, it is not a dedicated room: it is a second-hand piece of furniture, adapted. Inside there are fifteen or so mother plants plus whatever is being propagated. Here is how it is built and what I would do differently.
The cabinet
I needed glass on three sides for the light and doors that really closed, to hold the humidity. Living-room display cabinets cost a tenth of a terrarium of the same volume and are already built that way. The only structural change was taking out the chipboard base, which would have swollen within a month in the damp, and replacing it with a rigid plastic tray that catches the water.
The lighting
Four full-spectrum LED bars mounted under the shelves, not on the cabinet ceiling. It is the choice that changed the most: lighting each shelf from the shelf above, every plant gets light from close by, instead of one in the sun at the top and the rest in shade below. I run them twelve hours on a cheap mechanical timer which, unlike the smart ones, needs no network and does not forget the time when the power cuts out.
The humidity
I do not use a humidifier. The tray at the bottom with wet expanded clay, plus the doors closed, holds steadily between 70 and 80 per cent, and the glass tells me at once if I am overdoing it: if it condenses all night there is too much standing water. A five-volt computer fan, run off a phone charger, turns at low speed and is enough to stop the air stagnating. It is the eight-euro part that solved the biggest problem.
The monitoring
A thermo-hygrometer inside, among the plants and not against the glass, because the temperature at the glass is not the one the roots feel. I look at it morning and evening. Measuring is ninety per cent of the craft: without numbers you are only guessing.
What it costs
The second-hand cabinet, the LED bars, the timer, the fan, the thermo-hygrometer and the tray come in altogether under two hundred euros. That is less than two variegated Alocasia.
What I would do differently, which is the useful part.
I would get a deeper cabinet. Thirty-seven centimetres feels like plenty until you put the pots in two rows and can no longer reach the ones behind. Fifty would have been right.
I would put the LED bars on a rail or adjustable screws instead of fixing them. Plants grow, the right distance changes, and as it is I have to dismantle something to raise a bar.
I would buy two thermo-hygrometers straight away instead of one. One high, one low: the difference between the two shelves is several points of humidity and I worked that out late.
I would not put the cabinet against an external wall. In winter that side is three or four degrees colder and the plants in that row grow visibly more slowly.
And above all I would leave more empty space. I filled the cabinet in the first two months and since then every operation, every repotting, every cutting, is a puzzle. A nursery at eighty per cent capacity you manage; one at a hundred you endure.