354 points by cdrnsf 7 days ago | 101 comments on HN
| Mild positive High agreement (3 models)
Editorial · v3.7· 2026-03-15 22:46:44 0
Summary Free Expression & Access Acknowledges
This content documents a personal DIY hydroponics project implemented in a repurposed server cabinet. The page exemplifies freedom of expression through candid, accessible technical documentation published without apparent restriction. Beyond the structural support for unrestrained publishing, the content engages minimally with human rights frameworks, focusing instead on practical technical instruction and personal narrative.
Years ago, when California had a really severe drought, I saw a large version of this to grow grass for horses. It had a stack of trays with lights, and each day, you harvested one tray, fed your horse, and replanted the tray. It was only cost-effective when grass hay was really expensive.
Singapore is currently claiming title of "world's largest (and tallest) indoor vertical farm" with a five story, two hectare automated racked site (Jan 2026):
Is that a subtle 5th Element reference in the crontab?
This is fun!
The following isn’t a knock on anyone doing cool stuff like this: I’ve avoided any sort of tinkering and automation of my gardening because I find gardening to be a slower-moving, meditative escape from technology. My brain shifts into a different mode (almost a flow state?) when I’m out working in the soil and tending to my plants.
You did mention the reason for a server rack as a matter of circumstance. But if I were to do and really want the Hydropnics part, I’d sell the Server Rack (good price) and buy the cheaper Pallet Racks. The first thing that comes to mind is that it will be easier to plan, pluck, change lights, etc.
Server Racks - you don’t interact with them often, but you will need to with the Hydroponics one.
Also, your setup is too clean. Water will drip, spill, the pebbles will fall. Looks really nice, though.
About 5 years ago, I worked with a Climate Research Scientist friend, growing exotic plants in dutch-buckets, tower aeroponics, and rack mounted red-lit setups to induce Vitamin B-12 (only found in meat, so deficiencies develops in vegetarian) to Spinach trying to produce Super Spinash.
I also built something similar. In the end I appreciated the services our nature provides to us even more. Replicating all this artificially is really hard and energy intensive. Planting and growing plans outsides is fun and rewarding; adding all the tech in the end felt like a big waste of resources.
My motivation to work on such a project was my disbelief in human mankind to keep our planet earth habitable.
I know this was about the journey, but for anyone interested in home hydroponics (without the journey of building it), I have had a Gardyn[1] for 6-7 years. It works well. It has a 6 gallon (20 liter) tank and a couple of strong vertical growth lights, in a sleek package that looks good in the home. Plants are fitted into pods, in standard-size rockwool blocks that you can get from any grower shop.
The fact that it works at all after a number of years, is surprising to me, given everything that goes on with it: You've got a moist environment with water pumped through it multiple times a day, fertilizer in the water crusting up in places, living plants with their roots growing into the pipes, algae growth, and a lot of parts that are shuffled around often.
There might well be other systems around these days that are the same or better, I wouldn't know, the Gardyn is just what I ended up with when I researched it years ago and I'm happy with it. For downsides, seeds are expensive from Gardyn, but you can plant your own. I do buy some from Gardyn because they have a big selection, and they usually come out good, which regular seeds often don't for whatever reason. They try to push their subscription service but I don't need it, so don't use it.
Hope this doesn't come off as advertisement, as I said there may well be better options (would like to hear about them), but this one works for me for a pretty hassle-free experience.
Setting aside the DIY and hacking spirit of the project, let's remember that, with the commonly accepted figure of 2,500 kcal/day for an adult male, a whole iceberg lettuce (~600g) provides about ~87 kcal which is roughly 3.5% of what one's need.
I've also tried a few different ways to grow plants indoors and I'd like to share my experiences for anyone interested. I like to grow indoors since I can do it year round and the environment is clean, stable and there are no animals or bugs (knock wood). Over time, I've gravitated towards low-maintenance hydroponics. Growing in soil needs soil, which is also dirty and so a bit more PITA, and it can harbor bugs.
One setup I had was a vertical (hydroponic) window farm, which looked pretty great, but the roots start to get into the tubing, which I suspect could happen in the rack-mount system too. It also wasn't simple to just take out one plant for maintenance.
A small NFT (nutrient film technique) box has worked very well, requires very little material as substrate and is easy to maintain. Might get problematic if growing the same plants for over a year since the roots can grow a lot and basically partially outgrow the system so the flow of water starts being insufficient and therefore might need at least some trimming and replanting if some of the roots start to suffer.
I'm in the process of trying out deep water culture, which requires even less materials since there's no growing medium, just water, and roots are submerged so doesn't have the same issues as NFT. Probably has it's own problems, though, and air pumps can be loud!
Anyhow, most of my plants are in a passive hydroponics system. "Kratky method" is something a bit similar. I basically replaced soil in pots with clay pellets and manage watering so that I have to water every 2-3 days. Requires clay pellets as the substrate so needs a bit more effort up front, but doesn't require electricity and is more portable when using small/medium sized pots. Pellets can be reused (at least most of them). I also added a short tube for monitoring water level and possible maintenance if I need to wash / flush the pot with the plant in it.
Regarding fertilizing, I rarely do any accurate measurements anymore. I got a few pump bottles and measured how much fertilizer one push gets me and wrote on the bottles how many pushes per litre. I also eye-ball the water color a bit since I know how it should look like.
Oh, and the plants that have done well for me, and can grow for a long time with multiple harvests (so no lettuce): peppers, cherry tomatoes, cucumbers, trying some small strawberries
Yo. I successfully did outdoor aeroponics with insane temperatures in the root chamber (near 40°C/100°F). My secret? I grew 'Virginia Gold' tobacco.
> Farmers discovered that bright leaf tobacco needs thin, starved soil, and those who could not grow other crops found that they could grow tobacco. Formerly unproductive farms reached 20–35 times their previous worth. By 1855, six Piedmont counties adjoining Virginia led Virginia's tobacco market
This is one beast of a plant. My plants stayed alive when I stopped spraying water in September and only died because of frost in late December. They were about 40 cm high due to the small volume of the root chamber.
Anyway it's a great choice for an outdoor aeroponics setup.
I played around with hydroponics. in the end, they never ended up better than dirt. with dirt you have to water it, and fertilize every few months, but that's it.
with hydroponics, every week I was refilling the water, and adjusting the EC and pH. The end result was very similar to what dirt got me
There have been vertical farms in Singapore that went bankrupt previously. I don’t think this model has worked very well in general globally, compared to traditional farms. This particular one is producing insanely expensive produce. For example the lettuce that is mentioned is over $14 a pound. It’s also a hydroponic farm which means only some crops can be grown.
I wonder if they are profitable, or if some sort of government support is involved. I don't think power for all those lights is particularly cheap in Singapore, and the competition in the surrounding countries has cheap labor and lots of free sun and rain.
Gen Z will often write like that, feeling that using capitalisation feels too "formal" for non-professional communication.
It's feel just the next evolution in our written messaging dialect. Gen X had c u l8r?. Millennials didn't have to pay per character, and got full qwerty keyboards so opted for normal sentences. And now Gen Z have decided that auto-capitalisation is unnecessary.
Having it closed (like this server rack) allows for controlled air circulation if fans are installed and flow paths are designed properly. Also, in case heating is needed, for example, if operated in the basement the heat loss can be reduced.
I found it pretty hard to read without the caps. I guess the punctuation mark is too small for my elderly eyes, and my brain sees it like one gigantic sentence. Perhaps the author of the blog is a fan of Kafka?
I’ve seen this popping up in a few areas. In harsher winter conditions there are some small time farmers using this method to supplement their feed during bad winters.
Tell me more about super spinach. B12 doesn't come from plants or animals, but from bacteria. So, I don't know how you could get B12 into spinach by using red lights. You'd also need to introduce the bacteria and somehow make it live inside of the spinach.
Do you have some sort of inoculation step and then use red light to penetrate the spinach leaves to feed light energy to the bacteria?
If you have cheap energy, this can be much more water-and-space-efficient than farming outside by eliminating pests and weeds and providing an ideal growing environment for the particular plant year-round.
I've spent some time looking into all these methods before, but all of them required substantial amounts of plastic in contact with plants/water and in full sun/heat. Are you worried about leachables?
To be clear, I'm not asking this in some new age way, and I'm sure it's better than the amount of pesti/herbicides used traditionally (and the whole movement behind hydro/aquaponics is fascinating to me), just wondering if this is something you ever tried minimising with such setups?
For some reason I had it in mind that growing tobacco was illegal in the UK, so your post prompted me to check and lo! Apparently it's entirely legal, for personal use.
So now I have a new project - I've always wanted to smoke 'pure' tobacco, like the ancients.
I'm twenty years too old to have an illegal harvest at home :)
Content exhibits mild positive signal toward freedom of expression through public sharing of technical knowledge and unconventional personal project. Author publishes detailed experimental methodology without apparent restriction or fear of suppression. Tone is candid and self-directed rather than constrained.
FW Ratio: 60%
Observable Facts
Author publishes detailed technical documentation of an unconventional agricultural experiment on a public-facing domain.
Author includes personal narrative, candid admissions of mistakes ('this is, for many reasons, a terrible idea'), and self-criticism ('this is not a serious guide').
Page contains humorous framing and honest reflection on project outcomes without apparent editorial pressure or censorship.
Inferences
The author's willingness to publish candid technical details and acknowledge failure suggests an environment permitting unfettered expression of ideas.
The conversational, first-person tone and lack of formal disclaimers indicates editorial freedom rather than institutional constraint.