Around 2019 the press was certain that by 2030 cities would grow their food in skyscrapers. We now know how that ended: Germany's Infarm cut more than half its staff in 2022 and withdrew from most markets, AppHarvest filed for bankruptcy in 2023, AeroFarms went through Chapter 11 the same year, Fifth Season shut down. The technology did not fail — the arithmetic did.
So the more honest question is: which parts of that story actually work? The answer is surprisingly concrete and, for someone growing at home, mostly good news.
Why industrial vertical farming stalled
Everything breaks on one number: how much electricity a kilo of lettuce costs under artificial light. Real figures from closed farms sit around 8–15 kWh per kilo of leafy greens, a daylight greenhouse needs a fraction of that, and a field essentially nothing. When EU wholesale power prices jumped past €200/MWh in 2022, the margins vanished overnight.
| System | Energy per kg lettuce | Water per kg | Yield per m² per year |
|---|---|---|---|
| Open field | ~0.1–0.3 kWh | 150–250 L | 3–6 kg |
| Greenhouse (daylight) | 1–4 kWh | 20–40 L | 30–60 kg |
| Closed vertical farm | 8–15 kWh | 2–5 L | 80–250 kg |
| Home tower at a window + LED | 0.3–1.5 kWh | 3–8 L | 20–40 kg (per m² footprint) |
Home growing escapes that trap because it uses daylight as the base and LED only as a top-up — and because you pay for no warehouse, no cold chain, no delivery. Your lettuce travels three metres to the plate.
Water and climate: this part is not hype
Here the numbers are hard. Agriculture accounts for roughly 70 % of global freshwater withdrawals; across southern Europe summer droughts increasingly mean garden watering bans. A closed-loop hydroponic system returns the solution to the tank and loses water essentially only to evaporation and transpiration — measurements show 80–95 % less water than soil growing for the same amount of leafy greens.
- 40 L tower: roughly 2–5 L top-up per week in summer, less in winter — depending on plant count and size
- 50 L tower: fewer top-ups, more thermal inertia in the solution, safer when you are away for a week
- Same footprint as a 40 cm pot, but 32 planting sites because you grow upward
- No fertiliser leaching into groundwater — the surplus stays in the tank and gets used up
The second climate reality is heat waves. Above 28 °C the solution in the tank holds less and less oxygen and the roots suffer. That is today the most common reason home systems collapse in midsummer — more common than any pest. What to do about it is covered in the piece on germination and temperature and on water quality.
The EU framework: what is actually changing
European regulation moves in two directions that touch hydroponics directly. First: Regulation (EU) 2018/848 on organic production still does not allow the organic label for soilless growing — hydroponic vegetables legally cannot be certified organic in the EU, however cleanly you grow them. That will not change in the foreseeable future.
Second: the Farm to Fork strategy calls for at least 50 % lower nutrient losses by 2030, and the Nitrates Directive already limits nitrogen leaching. Closed systems sit on the right side of that, because by definition they release no solution into the environment. Expect recirculating growing in commercial greenhouses to attract support — not because it is fashionable, but because it is the easiest way to meet nitrate obligations.
Sensors and automation: how much do you really need
Electronics got brutally cheap. A combined EC/pH meter that cost €300 in 2015 now sells for €40–80. Permanent tank probes that push readings to your phone start around €100. That is the real, tangible change of the past decade.
| Level | Equipment | Price | Worth it for |
|---|---|---|---|
| Basic | Handheld pH and EC meter + calibration solutions | €40–90 | Everyone — this is not optional |
| Middle | Digital timer, tank thermometer, spare pump | €20–60 | If you travel often |
| Advanced | Permanent probes with an app, auto-dosing | €150–600 | From 3–4 towers upward |
Honest verdict: automatic pH dosing on a single home tower is wasted money. You replace the solution every 2–3 weeks anyway, and correcting it by hand takes two minutes. A sensor that tells you the pump has stopped is worth far more than one measuring pH to three decimals — twelve hours without flow in summer kills plants, while pH 6.3 instead of 5.9 kills nothing.
What of all this reaches you
- Cheaper, better LEDs: good horticultural diodes went from about 1.7 to over 3.0 µmol/J in roughly a decade — same yield on half the electricity
- Quieter, leaner pumps: modern small circulation pumps draw 5–10 W and stay below 30 dB, which is the precondition for a tower standing in a living room at all
- 3D printing: the complex geometry of a 32-site tower is now produced locally from PETG, with no injection mould and no ocean freight
- Knowledge: nutrient recipes that used to be trade secrets are public — see nutrients
Vertical farms did not fail on physics. They failed on electricity prices and interest rates. At home those two line items look completely different.
Realistic conclusion: nobody is going to feed a city from a tower block. But growing your own lettuce, basil, lamb's lettuce and rocket year-round on half a square metre is routine in 2026, with kit that costs less than a year of shop-bought salad. If you want to know how soilless growing got here at all, read the history of hydroponics.