Update On Hydroponic Tiny Garden

About 2 weeks ago, I posted a photo of my Hydroponic Tiny Garden. I’d just “planted it” by putting the rock wool cubes into the net cups (after starting them less than a week prior). So we’re about 3 weeks total into this. I’d also put in place one “transplant’ from the experiment with a Bag-O-Dirt in a tub as a lettuce grow. At that time it was about 2 inches across, all told.

Well, here’s an updated image. I’m very happy with the results so far.

In the front row we have (left to right) 2 lettuces doing nicely, 2 failed cups, a nice kale / cabbage cross using paper as medium, one of them that has failed. The failures were, IMHO, from my setting the cubes in the tub with zero “hardening off” time just before a sudden hot day and doing so with too little growth. These things were barely sprouted. This whole row is in 2 inch “net cups”. It gets the most sun latest into the afternoon as the shadow line starts on the other side.

Second row starts with the lettuce transplant, then several of what I think are the Senposaai oriental greens that are quite happy. (note to self, make more notes to self about what was sprouted ;-) These, and the back row, are in 3 inch net cups with the depth adjusted using canning jar rings.

In the back row is one pea plant (testing the viability of short bush sweet peas), then 3 more lettuces, and a senposai.

Hydroponic Tiny Garden at 2 weeks

Hydroponic Tiny Garden at 2 weeks

The image is a bit high contrast as it was a very sunny afternoon so lots of direct sun off of white styrofoam. Still, I think you can see that the lettuce in particular is doing great. The older transplant is nearly to the point where it can be harvested for a salad. It is being grown as “cut and come again’ so I’ll not be killing it in the process of a harvest, just trimming off some leaves. Note that, for scale, the rings around the back two rows of pots are 3 inch “wide mouth” canning jar rings.

The other “from seed in rock wool” lettuces are a bit bigger than the transplanted one was at the time of transplant, so that’s saying to me that I can get a LOT of lettuce in about 4 to 5 weeks total this way. Good normal harvest size in about 6 weeks. As an “Aw Shit Happens” need for emergency food supply, that’s just crazy fast compared to “dirt gardening” here. Admittedly, you will NOT be happy on just lettuce; OTOH, you will be a lot happier with a lettuce side salad with your dry beans and rice dinner ;-)

For comparison, here’s the prior image:

Hydroponics in a construction tub

Hydroponics in a construction tub

As you can see, the growth in 2 weeks has been quite impressive.

The Bag-O-Dirt lettuce has been doing very well also. We’ve had about 4 total salads from it. I’m talking full plate of “it is your dinner” Chef’s Salads, not dinner side salads. It is almost ready for another cutting. The last cutting did have some tiny bugs in the lettuce. Aphids I think. Little dots that fell off in the wash water soak. So growing in tubs has eliminated the very big bugs and snail issues, but not the tiny ones. I’ll likely need to set up an indoor lettuce grow on a “bread rack” to avoid all bugs.

For now, it’s easy enough to just toss the lettuce in a tub of water and let the little buggers swim for it ;-) They are not making holes in the lettuce (like the big bugs) and they wash off pretty darned easy. Better that than eating pesticide sprays (IMHO) as there isn’t a lot of time for any spray to degrade between harvests. We’ll see if my attitude changes as the complexity of the population evolves…

I’m running the Bag-O-Dirt as a quasiponics system. It IS a small bag of potting soil, just laying there; but I water it once a week or two with Miracle Grow and added some MgSO4 (Epsom Salts) to it. Most days I just sprinkle with fresh water and put about 1/2 inch in the bottom of the tub to soak in over time (through holes punched in the bottom of the bag). It is working quite well, but water consumption is much higher than the hydroponic system that has less exposed wet area.

In the future, I’m more likely to start seeds separately and only transplant about one every 6 inches into the bag, and that via one or two inch holes in the top side, not removing the whole plastic surface. that ought to significantly reduce evaporative water losses. Float a styrofoam cover over the area not covered by the bag to save even more water.

For easy set up (especially in a hurry in an Aw-Shit) the Bag-O-Dirt is very much easiest and fastest. IF you have time to prepare the hydroponic system in advance (so the styrofoam boards are drilled and ready, net cups in hand, etc.) the hydroponic system is just super fast to assemble and get running. Either one ought to work well indoors with LED Grow lights.

I’d GUESS that with some care and a bit of intensive operations you could keep a couple of people fed with a “grow room” of about 10 x 12 feet or about a “bedroom size”. Or, if your garage doesn’t over heat in summer or freeze in winter, in one car space in the garage. It would take a fair amount of capital investment for all the “bread racks”, LED lights, tubs, cups, etc. But I think it would be well worth it. Plus you can start with one tub and only add more as each one returns a “profit” in food.

That “grow room” would be dependent on continued supply of power and water, so not really useful in a complete collapse of the society. Then again, it can take a while to reach that point… when it might well be that “suddenly” a lot of dirt becomes available and empty… Look at Venezuela. Despite all the news about power failures, it was only a few days in a row. Mostly power has remained even while people had very low “rations” of food. Indoors, water use would be very limited as evaporation would be quite low too. When not in operation, it’s just a nested stack of tubs, a bag of hydroponic fertilizer, and a stack of cups and a “storage room” of racks. Nothing to see here, move along…

In Conclusion

This is really the first time I’ve been successful at growing salad fixings. Mostly due to dryness issues of the soil and bugs / snails. I have grown some lettuce before, but only a few and often with leaves with holes in them. Yeah, I know, use a lot of sprays… but I don’t want to eat a lot of sprays…

So this has me very happy. Yes I CAN grow a salad after all. As we have been buying Bag-O-Salad at about $2 / week, this is a $100 / yr “win” for me. I’e got about 8 months of “outdoor grow” time all told before I’ll need to have some LED lights and a place inside for winter salad. Just the notion I can have DIY Fresh Salad year round it “worth it” for me.

Also, the spouse was ecstatic over the lettuce quality from the potting soil bag grown lettuce. No more soggy, wilty, sad salad from a few days old bag in the fridge. This had that wonderful fresh full flavor in butter soft leaves that you can only get on a fresh pick. I’m expecting the hydroponic salad to be the same. Even if every other plant I try fails, just the lettuce alone is worth it for me.

What’s next?

I’m not sure. I’ll be slowly improving my lettuce technique. I’d like to add some other kinds (Romaine in particular. The spouse likes butter lettuce soft, I like Romaine crunch ;-) Then there’s choy and other stir fry greens to add. It looks like the one pea plant is doing very well, so some “Little Marvel” peas at about 1 foot tall might be fun (lots of 2 inch net cups on close centers needed though…) It would be nice to demonstrate something with more protein and starch content for a more complete meal base.

Having also documented the failed cups, I’ll be replacing them with something else. Most likely some herbs. Oregano, Basil, etc. There’s one complication here that will arise eventually. Many plants put chemicals / hormones into the soil round them to “claim” the dirt. I need to review my “companion planting” rules to find out “who kills whom” and only put compatible things in the same tub. So, for example, I want to try some green onions with ‘a few’ in a 2 inch cup; but I know that “peas and onions” don’t get along so well in the dirt. That means different tubs.

Having shown that the basic system works really well, and fairly easily, I now need to move on from the “don’t waste a lot of time just throw some stuff at it and see what you think” rapid prototyping stage to the “plan carefully what you want and run this as a professional operation” stage. I can likely get 2 x the lettuce growth by putting a ‘bubbler’ in the tub, for example. In the short run, just a tablespoon of hydrogen peroxide can keep the roots oxygenated, but in the longer run an air supply and bubble stone is cheaper.

I’ve still got enough styrofoam boards to set up two more tubs, so I’ll be doing that as I think of things I want to grow. There’s a small gap between the styrofoam boards and the tub walls on the long axis, I ought to make a cover for that so that algae doesn’t get light in the tub. Details to polish here and there. Algaecide to buy?

Eventually (in about a month? maybe two?) I’ll reach the point of needing to deal with “spent” solutions and how best to do that. I intend to just dump it on the dirt garden so no nutrient is wasted. Then wash the tub and set it up again. At that time I can also go to “just one size cup” in any given tub. I’m leaning toward 2 inch cups as my general standard. So far I’m not really growing anything that looks like it needs a 3 inch diameter base. So future tubs will likely be all 2 inch holes / cups. The 3 inch reserved for use in Kratky Method jars. ( I have two on my windowsill for experimental things at the moment). I’m not seeing any issues with that stage.

I’ll need to try some different nutrient mixes too. Find the most growth for the least cost and fuss. Even using the boutique liquid mix, this is a big win. The less costly dry mix will be essentially irrelevant as a cost basis.

I’m not quite ready to make the leap to pumped systems with PVC pipes in a “grow wall”, but I can see it in my future. Less total water and nutrient mix needed. Less weight. Better yield. Looks way cool too ;-) Between there and here I need to settle on what I want in my salad, which plants “play well with others” in the same solution, and just what my interests are in this. Daily salad? Peas and other ‘real food’ in an Aw Shit situation? Play Time for Me? Low cost year round garden? Maybe all of the above?

Frankly, THE biggest surprise for me has been how much labor savings are involved in this. No digging. No soil prep. No weeding. No constant daily water check and watering (especially on hot days, the squash in pots needs a lot of daily water). It has just been “set it up and walk away” so far. I did need to put about 1/2 inch of water in a few days ago. Compared to an inch a day for the other stuff in pots, 1/2 inch in 2 weeks is nothing for makeup water. (The Kratky Method tub doesn’t even need that…)

So there you have it. I’m happy. I’m sold on the method. I’ll be doing more and working on an inside (even if smaller) grow area for winter salad in the longer term.

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in Emergency Preparation and Risks, Food, Plants - Seeds - Gardening and tagged , . Bookmark the permalink.

30 Responses to Update On Hydroponic Tiny Garden

  1. Graeme No.3 says:

    Another possibility is plastic pipes (although I would prefer polyethylene or polypropylene rather than PVC as I dislike metal salts lubricants in them). A hole saw makes space for your cups.
    Work out how to keep the pipes stable. (hint right angle bend, short connection to another right angle at 90 degrees. Gives you a way of adding solution.)
    You can set up a series of (shortish) pipes and grow plants in one pipe and anything antagonistic in another pipe, so limited bench space taken up.
    Alternately you could connect them and trickle feed solution through them to a ‘drain’ tank. By raising the drain tank and lowering the feed tank (at the other end) you get a supply of feed solution without the need for electricity (except for your grow lights). I used the idea in a greenhouse because we still get some sunlight in winter here and no snow (although I am wondering what this coming winter will bring) but it really needed warmer conditions and more light.

  2. E.M.Smith says:

    I was thinking something like these (though maybe made with ABS drain pipe…)



    and more:


    So I’m thinking a square of fat pipe for the base (like 8 inch fat) that is also the tank for nutrient solution. Put a tap in the thing somewhere for draining and have a clean-out in one corner. Then, from one or two “street Ts” have a riser to a set of back and forth runs with plants of about 4 inch pipes.. These join at the top for stability, with another clean out and fitting for the pump, that gets fluid from the bottom (yet another fitting) and pumps it to the top to run down in NFT (Neutrient Film i.e. shallow).

    Just imagine a couple of square spirals (DNA Helix like) twining there way around a couple of turns. Small connecting pipe to stabilize the top. Large pipe making heavy water / solution filled base. Pump on the side with timer. IF it needs it, you can cut chunks of pipe with a semicircle in the end (crossways) to use a braces between “turns”, but I don’t think lettuce and 1 cm of liquid will be enough weight to cause a 4 inch pipe to flex much…

    That’s sort of what I’m thinking about.

    Somewhat of a “plumbers delight”, but then again, pipe is easy… and sewer pipe connection styles are intended to have some rise over run… 4 inch pipe ought to take a 2 inch cup nicely while not being too expensive. The use of 8 inch base for stability and as tank adds costs as it is not cheap (compared to a 17 gallon tub like folks usually use at $10) but I like the idea of all one material and all one construction / method ;-)

    That’s what I’m thinking about anyway…

    Issues yet to address:

    Size / cost of “pipe as tank” for about 15 gallons or more of solution.

    How many turns / what pitch before it isn’t stiff enough and needs braces?

    Is one cleanout on the bottom enough?

    Protocol for filling / empty of “tank”.

    Is black going to be too hot in the sun? (Alternatively, how much lettuce needed to cover the black?) or is it a feature in cooler seasons? (Paint to fix if needed).

    Can it be made to disassemble non-destructively into “station wagon sized” parts?

    Any baffles needed to deepen fluid level at any point? (Related: Are two feed points needed so non-level effects don’t make one side of the helix starved?)

    Am I really that interested to do this work?

    Is it really that much better than tubs with bubblers? Yeah, it does LOOK cool though…

  3. E.M.Smith says:

    Oh, and another small note:

    I did a test germination of some cheap green onion seeds. About 80%+ by eyeball germinated.

    What makes this special? I bought these in 2000 specifically for a long duration germination test series. Onions are notorious for having a short seed life. 1 to 2 years is the stated period.

    These were on clearance end of season at 10 ¢ / package so I bought $1 worth. “Better Homes” brand of “White Bunching onions”.

    They have only EVER been in the refrigerator except when a packet was removed to test germination.

    Last test was at least 8 years ago. I expect these to be duds. They were definitely not. At 18 years they are still germinating in large numbers.

    So, OK, probably enough of an experiment. I’m keeping the rest in the fridge and MAY do this again, but frankly, at 18 years, what more do you want?

    This give me great hope that all the other seeds I stored in the fridge as I ran out of freezer space will be just as viable. In any case, it’s darned strong evidence that if all you have in your prepper kit is a jar of seeds in the fridge, it’s probably “Good Enough” for many years.

  4. Graeme No.3 says:

    If you don’t have electricity available the simplest method is a container at each end connected to your trough by a flexible hose. One container (full) is lifted up and runs solution into your trough and out the other end into an emptied container at a lower height.
    Set the connections in the end plate above the bottom of the trough so it doesn’t drain completely. You might be able to work out how to control the flow rate into the trough (I couldn’t get it to work reliably). It also depends on how keen you are to lift those containers and how often you do it, but a few weeks workout will save on gym membership.

  5. Larry Ledwick says:

    That is cool to hear, given the small size of the potato seeds I got, that gives me confidence that my little glass vials in the freezer will keep them as long as I will be able to dig a hole and plant them.

    The tiny size of onion seeds also lends themselves well to those small 1 dram or 2 dram vials you could put hundreds of seeds in even those tiny bottles.

    Your experiment also implies that heat is the enemy that kills onion seeds. Being so small if they become biologically active at room temperatures they will quickly exhaust the stored nutrients in the seeds. I wonder what the temperature is that seeds go essentially totally dormant. I know in the ark depository they keep them very cold.

    Locally mined coal provides power for refrigeration units that further cool the seeds to the internationally recommended standard of −18 °C (−0.4 °F).

    Hmmmm very interesting paper on the effect of temperature and germination rates. It appears that some seeds can be encouraged to germinate by a heat cycle above some threshold temperature. For fire adapted species this is fairly high, for non-fire adapted species temperatures close to summer heat wave conditions work.

    (makes sense this would force bloom of new growth after a heat wave killed off a large fraction of growing plants.

    Likewise I know that for some plants the seeds need to experience a winter cycle of below freezing temps before they will germinate (some trees require a chill cycle to turn on germination in the seeds during the following warm wet cycle)

    It might be useful to thermal shock seeds with a few days of summer time temperatures before initiating sprouting by soaking.

  6. Larry Ledwick says:

    Another related seed germination paper:


  7. E.M.Smith says:

    For most garden seeds, it is enough to just put them in dirt, get them wet and have it be spring temperatures. There are some with exotic cycles, but most of those are not garden products.

    Some that depend on fire are sensitive to a chemical that is made in fire. You can actually buy a smoke extract to get them to germinate.

    Some (especially big fruit with hard shells) need “scarification” so you scratch or sand the surface. Some tree in New Zealand was on the verge of extinction and then they figured out it depended on the Moa to scarify their seeds but the Moa was now extinct. Some scratching later they got seeds to germinate and new trees were produced.

    As you pointed out, heat cycling matters for some.

    Tobacco needs exposure to sunlight or it will not germinate. Dust sized seeds so likely an adaptation to wait until on top of the soil and not try to germinate if under anything.

    Then there are the “recalcitrant’ seeds that can not be dried out. Mostly fruit trees. They must be planted fresh. Oranges, for example. Very hard to store for a long time. Usually “preserved” by having a minor orchard as the plant itself has a longer lifetime. Recently, saving tissues for cloning has caught on.

    Then there are bulb formers… Onions only form a bulb and go dormant based on the length of day being “right”, so you buy onions matched to your latitude… Multiplier Onions divide into more onions when the bulb grows, but once dormant (i.e. dry and harvested) often need a cold cycle to start again. Right now I have 3 sections of a shallot in the ‘fridge. I’d planted and watered them in a very nice pot and….. nothing. They had NOT been refrigerated after harvest, which was a surprise. I’d assumed they had been in cold storage. So after a few weeks, I’ve taken them out of the pot and into the fridge. Usually one week is enough in the cold, sometimes two, to reset the clock to “It’s SPRING!”…

    For anything you have not grown before, it is often a requirement, and always helpful, to look up their germination requirements.

    It is part of why I like growing things. Solving the puzzles ;-)

  8. H.R. says:

    @E.M. – I’ve been enjoying the picture of your hydroponic garden when I stop by to check the comments. It’s kind of cheerful. As Bob Ross would say, “Happy little plants.”
    Pro tip for those bag-o-salads: When you open one up and use only a third or half the bag, put a folded up paper towel in the bag. It will extend the life of the remainder by 2X or 3X.

  9. Power Grab says:

    We have 2 tomato plants and one strawberry plant on our patio. We have lots of tomatoes! But we only get 1 strawberry ripe enough to pick per day, a few days a week. Some of the tomatoes are nice and red. One that wasn’t very red dropped off into the dirt, so I brought it in.

    Should we wait until the tomatoes are not only red, but also getting soft before harvesting them? We’ve never had more than one before.

  10. DonM says:

    The bottled water delivery guy told me (last week) that they have hundreds of cracked bottles that they would love to get rid of (he tells me that, because of the China thing, nobody wants them). Although OSU Ag people take a bunch they still have too many.

    If you need a starter mini green house in the spring (or any other reason you can think of), get the free cracked plastic 5 gallon bottle(s) from one of the bottled water companies in your vicinity to get your outdoor plants off to a good start; Cut the bottom off and just place over the plant….

  11. Graeme No.3 says:

    thanks for that tip. Here in South Australia our government’s devotion to “renewables” has forced electricity prices so high that all the recyclers has shut down business. Exporting waste isn’t working as overseas countries are now threatening to send back any garbage shipped there.
    This would help avoid vegetable losses in spring as frosts happen later than last year (or in the parlance of the local broadcaster ABC (always biased crap) “unprecedented cold spell due to global warming”.

  12. H.R. says:

    @DonM – Great tip on those plastic bottles.

    You could start your plants in 3″ or 4″ round pots, bunch them into a circular group, and then cover them up. Haven’t done the math on how many 3″ or 4″ pots a bottle would cover as I have no clue what the diameter of one of those bottles might be, but for home gardening, a half-dozen bottles would give cover to a nice little garden’s worth of plants.

    With the bottoms cut out of the bottles, they should stack quite nicely in the garage or shed until the next season.

    That idea sure would have saved me quite a few drowned plants this year.

  13. Bill in Oz says:

    Frost right now in the Adelaide Hills of South Australia at midnight…It will get colder before sunrise !
    Where the hell has our Gore Bull warming got to ?
    And thanks Don for the tip about the water containers. I’ve got my sweet potato starts in pots, inside away from the frost..I’ll be using your tip later on in Spring to give them some protection outside..

  14. Power Grab says:

    @ HR:

    Re “…I have no clue what the diameter of one of those bottles might be…”

    I would call the diameter of our bottles 9 inches (usable). There are some bumped-out rings that are larger than 9 inches, but I wouldn’t count that.

    Also, the usable height is about 12 or 13 inches.

  15. Pingback: Hydroponics First Harvest Time? | Musings from the Chiefio

  16. E.M.Smith says:

    @Power Grab:

    9 inches? ONE hand span? I think you may be talking about different bottles. I thought they were talking about the 5 gallon ones that go on a water cooler? I think they are a bit over 1 foot.

    Or maybe this is an American Size vs Metric thing…. all those tiny Euro-sizes and dinky servings ;-)

    I have a carboy in the garage (somewhere…) and if nobody else comes up with the diameter, I suppose I could go hunting for it…

  17. H.R. says:

    Power Grab & E.M. – Yup, I was guessing about a foot in diameter, but to figure how many 3″-4″ pots it would fit over, well an inch error would be a lot.

    I’ve never seen a 9″ diameter water bottle before. That’s about the diameter of my coffee cup ;o)

  18. E.M.Smith says:


    Product Dimensions 12 x 12 x 20 inches

    So yeah, one foot diameter. I’d figure a cross of 3 of the 4″ pots or 4 of the 3 inch pots, and then either 4 or 8 filling in the space between the cross. So 9 to a dozen 4 inch, or 16 to 20 of the 3 inch. If packed fairly tightly. Likely a hexagonal packing would work best…

  19. DonM says:

    It’s less than you would think … I can only get 10 little circles in a big circle (4 x dia) … drew it in cad program.

  20. H.R. says:

    Looks like I’d only need about 4 water bottles for my 8′ x 8′ garden.

    Now need to locate the nearest distributor so I can drop by when I’m in the neighborhood. I wouldn’t need any until next year, but if I wait until next March, I’ll forget.

    Does using empty 5-gallon water bottles count as ‘hydroponics’?
    “NO, H.R.! Now get off my lawn.”

  21. H.R. says:

    Hey, hey, hey! There’s a distributor in the same complex as our favorite movie theater, about 20 minutes away.

  22. Larry Ledwick says:

    Dense packing would be 7 small pots inside the carboy body, one in the center surrounded by a hexagon of 6, so small pot would need to be a tiny bit smaller than dia/3 or a bit under 4 inches if the inside diameter is 12.
    They are probably stating the size of the over pack box so ID of the carboy is likely about 11 or 11.5 inches.

  23. Graeme No.3 says:

    Dug out my copy of Romer – Hydroponic Gardening in Australia (2002 reprint).
    He says that some time in refrigerator for seeds before planting boosts germination.
    Also your float method should include aeration of the solution.
    He doesn’t seem too worried by some algal growth unless it could clog pumps and drain lines. Treats it as proof of good solution health.
    For carrots (& parsnips), marrows, melons, and taller tomatoes he recommends a 25 litre drum filled with inert media with a drain hole about 5mm. from the bottom and fresh solution added (from top) roughly every 5 days. Also this approach for potatoes (filling up following leaves until full).
    Weaker solution for leafy things like lettuce.
    Quite keen on running used solution to waste (or on garden beds) but then his company sold ready to use solution concentrate (as well as bulk chemicals to commercial growers).

  24. E.M.Smith says:

    @Graeme No.3:

    Yes! Many plants have an ability to detect winter, so they refuse to sprout until it has come and gone. They don’t want to sprout in a warm wet fall then get frost killed. Another reason to store your seeds in a jar in the fridge.

    I was reading up on root crops, squashes and such. They do seem better in the Dutch Bucket type systems. (What you described with media and drain hole with solution in the top from time to time) That is an order of magnitude more complex. Mandatory use of pumps, tanks, timers (even if human…). Then you are buying bags of “media” instead of potting soil. Perlite can cost more…

    So I chose to start with the absolute minimal approach and plants suited to it. Kratky Method, Deep Water, and no pumps or bubbler (aeration). You get reduced yield without the air, but so far that isn’t a problem. I suspect a bit of algae in the soup makes for some biological oxygenation…

    Having convinced myself that I can do this, and it is well worth it, ( https://chiefio.wordpress.com/2019/06/18/hydroponics-first-harvest-time/ ) I’ll now start climbing that technological and investment hill.

    First will be finding my old aquarium air pumps and stones and adding air, then a small indoor system with LED light for winter salads. Perhaps a tubular Grow Wall NFT Nutrient Film Technique made of PVC pipes . Eventually some kind of Dutch Buckets, but the videos on builds are all “Plumbers Delights” for very fixed installations, while I want more modular, portable, storable… so some design work required.

    Per nutrient solution: One big surprise for me is just how cheap it is. On any production decline it is reasonable to replace with fresh (remember most growers are doing this for production and profit, not maximal use of cheap fertilizer). It is something like one teaspoon to tablespoon per gallon. My tub is about 12 gallons. It costs about $1 per POUND of chemicals in the big bags. Basically, one nice lettuce pays for the tub of nutrient solution and then some.

    The local hydroponic shop is clearly catering to cannabis growers with fancy blends named things like Max-Buds and at about 10x the cost, but when I said lettuce, we went to the back wall with a 25 lb bag for about $35 ($25 on Amazon). A lifetime supply at my present use rate. I bought a 2 or 3 lb bag for $12 instead as it will cover me for a year or two… How many Tbs in 2 lbs? A Lot.

    I intend to run the solution until something yellows or just doesn’t grow. I don’t need optimal production, and don’t want to dump the water until I must. I want to know when that point comes.

    I’m also using pool pH strips. Ok and showed my tap water is fine with a slightly acid 6.x pH, but at some point a real pH meter becomes cheaper in the long run.

    Basically, this was the Rapid Prototype stage to prove viability of the concept at minimal cost maximum speed (a common Silicon Vally management thing for fastest tine to market and first mover advantage) and now it is time to do “redesign and incremenral improvement” longer term.

  25. DonM says:

    I measured the water bottle on the way out last night. 10″ across the bottom.

  26. Pingback: Hydroponic Update 26 June 2019 | Musings from the Chiefio

  27. Really like seeing the progress, looking forward to getting mine set up soon.

  28. E.M.Smith says:

    I’ve found that one of the more important issues is monitoring water / solution depth. It can be a lot lower than expected faster than expected, especially in the 5 gallon pails. It’s a bit of a pain to have to pry them open to check. With the floats, they tend to drop down in the tub until they hang up on the taper at the sides and ends.

    I’ll be making a small pvc pipe “floater” and putting it in a hole in the top of those without floats. I need to find some small pvc pipe though. I’m thinking a 1/2 inch diameter, with a cap glued on the end, inserted (cap down) into the hole in the lid from below. Then another cap just pushed on (no glue) on the top so it can be removed if desired.

    Then you can just look at each pail or crate and see what the water level is.

    Also, the crate with the added bubbler is doing better than the ones without. It does seem to use more water, though (no real surprise as the bubbles increase evaporation and you are pushing a steady stream of dry air in / wet air out). It’s isn’t a real dramatic improvment, but definite.

    Also, different species of plants have different acceptance bands for heat, solution concentration, oxygenation, etc. I managed to kill off several sage plants with “root rot” while other things in the float were just fine. I’d moved them to a new tub filled with new solution (that, it turns out, was mixed much stronger than the prior) and between that and being in full sun with warmer water, they keeled over. Ditto a couple of other odd plants in various circumstances (mostly as very small sprouts).

    What works well? Seems like anything in the cole group (collards, cabbages, choy, …) along with peas and celery. Green onions too. Oh, and lettuce does great. Tomatoes / tomatillos too. Basil just loves it.

    What has been problematic? Sage, cilantro, parsley. The last two likely from my planting them out too small or into too much direct sunlight or too strong a solution (though the choy didn’t mind and it was in the same tub… as was the celery).

    Clearly it works better to plant one kind of thing in a tub, and adjust each tub to the plant in it. So I’ve got a bit more work to do to get more optimized solutions & conditions for each plant.

    Also note that all solutions are not equivalent. You can’t just “mix per package directions” and go. Some are mixed a lot stronger than others and it’s too much for a sensitive plant. I suspect there’s a whole literature out there on finding the osmotic limits of each plant, best pH, and levels of nitrogen, phosphorus, etc. That, too, argues for “Pick a plant, learn it in detail, put it into production, get good at it” THEN add another plant.

    My approach gave the most learning in the shortest time (my goal) but at the expense of some less than great results in some cases. Like discovering my 5 gallon pail of tomatillos only had a few quarts of solution left via the expedient of walking out the door and seeing one of the plants a nearly dead fully wilted mess… It did recover, sort of, but… Monitoring water level would have prevented it.

    FWIW I now have a Very Nice tub of green onions. I could plant them at a much closer spacing for an onion only tub, and will likely make a special float just for them. For now, it’s working very well and my “onion problems” are a thing of the past. ( I had “issues” growing green onions for years as it is just too hot and dry here in summer and I would not soak them often enough or deep enough). I’ve also got choy doing great (a goal for the stir fry dinners ;-) alnd the lettuce is really likely the floats (Kratky tub not as much likely due to water level dropping issues).

    My biggest problem now is just getting off my duff regularly enough to start the right number of seeds for the right replacement lettuces and such at the right times; and monitoring the water level more faithfully.

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