Hydroponics test -- big Kratky barrel with eggshell, ash, and urine

OK, seriously I don't know where to put this but maybe someone will have some ideas or observations.

I started a small modified Kratky hydroponics test in May, essentially just a big barrel, and planted two cucumbers in it. I later added a tomato. But here's the "catch."

I'm not using traditional nutrients. I don't WANT to use traditional nutrients. As with all my other projects, everything has to be as close to home as possible, and I refuse to buy chemicals to import into my yard. So.

I did a bunch of research on nutrient values in various substances, and settled on eggshell, ash, and urine. Eggshell has calcium (almost 98%), protein, strontium, fluoride, magnesium and selenium. Ash has calcium, potassium (4%, approximately), phosphorus (2%), magnesium, aluminum and sodium. Urine is approximately 14-3-3 in NPK but has many other trace elements depending on the diet of the individual. I added a penny to each plant for copper/zinc and put a dime in the bottom. Whether those will have any effect, I have no idea, but I did it anyway.

Putting the ash, eggshell and urine together you get an NPK value of approximately 14-7-5 based on these numbers. The nitrogen number would go steadily down over time. I used the powdered eggshell, but next year I'm going to try without it, as most of what it provides is in ash and urine as well. I did run into a nutrient deficiency with sulfur and I used epsom salt for that, but I'm hoping I can find a source with what I can grow or collect. Cabbage? Garlic? I added vinegar to adjust the alkalinity from the ash.

The cucumbers are doing great and have fruit on them. The tomato struggled with the sulfur deficiency rather seriously but seems to be recovering. No blossoms yet, which I think is because of when and how the nutrient deficiency hit.

My question is, is anyone else working with "natural" nutrients for this kind of system? Or am I completely on my own here? In all my searches I haven't found ANYTHING on non-chemical nutrients for a hydroponics system. Every single article, post, question, is all about buying the necessary chemicals. Some people make what they call home-made nutrient solutions, but it just means they buy the raw chemicals and mix them on site. That's like saying you make home-made spaghetti because you buy bottled sauce at the store and cook the noodles at home.

My second question is, am I missing anything? Other substances that might provide more of the nutrients? Would compost tea work? Or would it just turn the tank into a stinky stew? Other possibilities?

The homework you have done (and your results) far exceeded my little test. Adding compost to mine did not create a stinky mess. I think about what i have available. One thing i will have available is the liquid after ocean fish are pressure cooked. I would think that would have lots of goodies. Clay is known as being mineral rich, so maybe a little clay rich soil.

Thanks for bringing this topic back up and taking the lead. No energy(input)  hydroponics done naturally has huge possibilities. I need to get back on it.

I wonder about putting the "nutrients" in a suspended bag rather than mixing them into the water. Water soluble nutrients might then leach into the water as they're needed and keep the non-solubles isolated. Since this is done without any kind of pump, I should think the absolute worst place for the nutrients would be on the bottom of the tank, which is where they would naturally settle. I see work ahead! :)

When I transplanted the tomato it sulked for weeks before it actually started trying to reach the water. In this sense, I think seeds may be better than seedlings as long as the water level can be kept high long enough for them to germinate.

I accidentally let the water level drop too far and the plants nearly died. They're recovering, but I took the opportunity to pull the tank and look at the roots.

The tomato root ball is very small, about 6-8 inches long and about half that wide. No wonder it couldn't get the nutrients! The cucumber root balls filled the bottom of the tank, but they were hit the hardest by the lower water level, possibly because they had fruit on them at the time. Both were loaded, and I lost it all!

I'm beginning to see blossoms again on the cucumbers, so that's hopeful.

Because of the sulfur deficiency I did some additional research and learned that garlic puts out sulfur compounds through its roots. So next year's test will include at least one where a garlic clove is planted with the primary crop plant to see if that solves the sulfur problem.

I've started two additional tests in ice cream buckets to test quantities for the nutrients.

I’ve been working on kind of a similar project.  I have a 55gallon barrel with the entire top cut off and a drain added to the bottom.  I filled the barrel with coconut husks, then added about 4 inches of soil.  I have tomatoes growing now.  It isn’t really hydroponics, but I’m just using the soil for stability and am feeding the tomatoes with compost tea.  I water by flooding the soil with about a gallon of tea about twice a week.  I run my compost tea maker continuously in another 55gallon barrel.  I use about 5 gallons a day total to feed all of my house plants, some yard plants, and my tomatoes in the barrel.  I do not buy any additives for my tea.  Instead I add just add all of my kitchen waste, about 2 liters per day including egg shells, fruits, vegetables, grains, rice, bread, paper, cardboard, coffee grinds, and tea bags.  My tea smells earthy (no bad smells) and is dark brown with a fair amount of biofilm.  The idea is roughly based on the organic hydroponic method developed by the National Agriculture and Food Research Organization in Japan in 2005.  There is some good info in the references of the Wikipedia article “organic hydroponics”.

Good reference, thank you. I'll check it out.

The cucumbers have recovered and now have blossoms on them again. All female blossoms at this point (which essentially means the plant is getting the nutrients it needs--male blossoms will be the majority when the plant is stressed), but we may still get fruit before the end of the season. The tomato has also recovered fully and is starting to get blossoms on it.

The small bucket with the bean plant in it is doing well. I had to put it outside because it wasn't getting enough sun in the window well where I'd originally put it and now the water is getting hot in the sun. Another thing to take into consideration--temperature control. But the nutrients are working. I'll take the test through the end of the season and see how it does.

We never got any tomatoes on the plant but it's still blooming madly. The cucumber has one left on it that I'm leaving for seed.

The 2nd test in the basement is looking good. The hydroponics nutrients here (in 1 gallon water) are 1 T urine (nitrogen), 1 T ash, 1 T vinegar (to cancel out the alkalinity of the ash), 1 T powdered eggshell, 1 rusty nail (iron), 1 dime (nickel), and 1 penny (copper). The first test died, probably because the planting medium dried out and it didn't have enough roots into the water to make up the difference. The bean roots grow very slowly so they might not be the best option for this kind of test. But I started with them, so I'll continue.

I'm starting a 3rd test with 1/2 T of everything. So far equal amounts seem to be working, but I won't add the nitrogen until the plant actually puts roots in the water.

Two of the three beans aborted. The third is currently ripening.

However, the plant is now showing signs of nutrient deficiencies. Phosphorus, specifically, as the leaves are starting to purple. Any idea if almond shells will provide phosphorus? Other easily accessible sources? I don't have access to fish or shell-fish.

The primary nutrients lasted for nearly three months--this bean was started in July on 1T of ash, 1T of powdered eggshell, 1 T of nitrogen (although I've given it nitrogen maybe once a month during this period). I have two more bean tests going, one has sprouted. Another test is basil. I'm getting interested in the way different plants react. I think the nutrients need to be renewed when flowering starts--another test.

Updates:

Test #1 died, probably because the planting medium dried out and it didn't have enough roots into the water to make up the difference.

Test #2 (the one in the comment above) is now dead. I decided to test a phosphorus additive (since that's the macro nutrient needed for fruiting) and apparently there was too MUCH phosphorus (or something) because within a day the water was a dark blue green and the plant couldn't breathe. The roots were completely coated with this muck, and already dead. I had to cut them off. The plant subsequently died. I used an almond shell ferment, since almond shells have a high level of phosphorus but it's bound up in the shells. I apparently used too much (1/2 c in a gallon bucket). This test ripened 1 bean, and I gained two mature seeds.

Test #3 is doing well. Same as above, except I added 1 teaspoon of almond shell ferment and more nitrogen when it started blooming. Currently has 8 beans, so far so good.

Test #4 is starting to get its secondary leaves. By the time it's mature enough to fruit I should know whether #3 is working or how it needs to be tweaked.

I’m getting used to the patterns. Once I get the nutrients straightened out so the plants can survive long term, I need to start working on production. What non-chemical nutrients does it take for a fruiting plant to really produce in a hydroponics environment? How much? By next summer I may actually be able to make this thing work!

I realized that each of the plants was dying at or just after fruiting, and putting it all together it didn't appear to be a nutrient issue. The root mass simply wasn't large enough to support the plant under the higher nutrient load with fruit on the plant. Another test showed that the roots completely stopped growing after the nutrients were put in the water. So I'm now testing not adding any nutrients until the root system is developed. The bottle on the left is one week older.

Thanks for documenting this!

Test #8 looks healthy, but the roots are dark (see closeup of the roots). #9 is struggling and I'm not sure why yet. Doesn't look like any kind of nutrient deficiency and it was treated just like #8 except with more root before I put the nutrients in. #9 had the same amount of nutrients as #8, 1t ash and 1t eggshell. It also has dark roots.

I decided the dark roots are a problem, so the two most recent tests (10 and 11) I've only used 1/8 t of ash and the same amount of eggshell. The roots stopped growing when I put the nutrients in but remain white and clean. The plants look healthy.

With the smaller amounts of ash and eggshell, the roots continued to grow.

This year nutrients were added at a rate of 1 T of the ash-eggshell mixture per tank, diluted with vinegar and water and left to soak, split across 5 tanks. Each of the tanks is at least 3 gallons. 2 tomatoes, two one year old rice plants that overwintered, 1 bean.

Garlic worked as a sulfur additive--worked TOO well. The plants are showing signs of sulfur toxicity. The larger tomato in this video, as of today, has growing internodes less than half an inch apart and is furiously putting out blossoms. I don't know if the blossoms are an effect of the sulfur, but it's essentially stopped growing.

I recommend natural farming inputs for fertilizer stabilizers.  they are water-soluble.


intro to natural farming:  http://culturalhealingandlife.com.www413.your-server.de/index.php?/forums/topic/17-an-introduction-to-natural-farming/

natural farming inputs;  http://culturalhealingandlife.com.www413.your-server.de/index.php?/forums/forum/29-natural-farming-inputs/

Another update. Last fall I created a phosphorus additive, which was an almond shell ferment. When I added it, within a day the plant was coated with green and blue scum and the water was choked with it. The plant subsequently died. That was 1/2 cup in a 5 quart ice cream bucket. This time I split the 1/2 cup between 4 larger buckets (each at least 3 gallons) and got essentially the same thing, it just took longer. I think the phosphorus additive has to be in much smaller quantities, and only added when signs of deficiency show themselves.

This year's update.

I learned that temperature control is REALLY important for hydroponics. I finally figured out that the thing killing the plants was that the water got too hot. In order to control algae and such inside the buckets I wrapped them in black plastic bags. Since the project was in the sun, the plastic bags heated the water to well over 100 degrees (hot to the touch) and the roots died.

With that under control, the tomato recovered and fruited. Everything else was already dead.

I then put squash seeds in two of the buckets and this is what they currently look like:

2020 hydroponics update:

The hydroponics project is Kratky hydroponics (no pumps) with natural (non-chemical) nutrients. I use primarily ash and eggshell (dissolved in vinegar), with a penny, a dime and a rusty nail in each bucket. Your choice of nitrogen supplement. Phosphorus additives will likely be needed when plants fruit, but I don’t have the details worked out yet. The phosphorus additive I have used (almond shell ferment) is way too strong. Even half a cup in a 5 gallon bucket caused an algae bloom and killed the plants.

It appears (tentatively) that the initial “dose” of nutrients works season-long for everything except phosphorus, nitrogen, and sulfur.

I learned this spring that garlic WILL provide sufficient sulfur–too much. So more tests need to be done. A garlic clove growing in with the main plant created sulfur toxicity, which was worse with the beans. I tried later using water that garlic had been growing in, but the results were inconclusive as the plants didn’t have a sulfur deficiency at the time.

At this point my main focus is trying to figure out a way to keep the water level up. When Kratky is used with greens it’s not such a big deal, as the plants die long before the water level falls. To keep the plants healthy the water level needs to maintain a constant level once the roots are established, but since each bucket is separate and wrapped in black plastic I have no real way of measuring the water level. I opened up one of the buckets and the water was almost gone, but when I refilled it the roots drowned.

So more tests next year, likely. Progress is being made.