Hydroponic Plants: Tips, Suggestions, and Techniques?

[maikeru]

A few weeks ago, I set up a very simple, but inexpensive partial/pseudo-hydroponics setup in my indoor garden room for the production of salad greens. I haven't experimented much with hydroponics except when I was a kid growing bean and daikon sprouts for salads. I have noticed some difficulties, like poor seedling germination rates and slower than expected growth. So far, it's not proven anywhere as productive as my garden or biochar plant pots, and that's disappointing...

Here's my current setup:

--Plastic container to hold a few inches of water
--4 small terra cotta containers per plastic container
--Using potting soil as growth medium
--Mycogrow compost tea given to plants (I keep a bottle of this brewing all the time now)

The terra cotta pots allow for air flow to the roots through their pores in the ceramic, hold the growth medium in place, and also wick moisture up so the soil never dries out. Have already proven this in practice. I don't feel like buying a pump or airstone for what is a small hydroponic thing meant to fit on a windowsill. I'm trying to keep this simple.

Trying to grow the following: kale, spinach, and swiss chards

However, I'm thinking of modifying the setup to this:

--Growth medium of chunk charcoal + perlite or 50/50 charcoal + potting soil
--Fertilizing with a diluted solution of blackstrap molasses to supply macronutrients like iron and magnesium

I have a few questions. Can you think of any other greens or small plants that would be great to grow hydroponically? And would current setup be better or do the modifications in mind have merit?

Don't want to use straight perlite because it cannot retain nutrients sufficiently and I am not using a nutrient solution as many hydroponic growers are doing, so I would like the growth medium to have some ability to buffer and store nutrients.

Any other suggestions or comments would be appreciated.

[Getting A Life]

Soil is no good as a hydro medium. it stays wet and promotes pythium and other undesirable organisms to proliferate. Many of these problem organisms are not present in hydro media. Air is critical, saturated medium systems incorporate high dissolved oxygen levels or ebb and flow designs with wet/dry cycles.

Some glomus species of mycorrhizae do well in hydro and will make a difference to your setup, glomus intraradices, glomus mossaea... so the mycogrow is a good choice.

Try a TP mix without the soil. Pottery, char, skip the bones...

If going organic you want a medium that is porous for microherd to inhabit. Hydroton, clay pottery, char, lava rock....

Plants in hydro can create water roots, these will convert to air roots fairly readily. however, they also develop air roots, which DO NOT convert to water roots. Water roots are those roots growing in the zone that is always submerged. Flooding above the water root line causes lysing of cells on air roots and they literally begin to rot. Upshot of this is unless you are using deep water culture or similar methods you should have a system whereby your roots are never submerged above a set level. Soaking is fine, saturation for more than a couple of minutes is not. Also, if your water roots are dried out for several minutes they become air roots, and then you flood them again - more problems.

Upshot is you want your water delivery system to be constant, and at consistent levels.

Wicking - yes - in soilless medium with lots of gaps for air.

Tomatoes love hydro, peppers, watercress, these are easy to grow and the watercress punches well above it's weight as a healthy food. Spinach. Did you know spinach grown organically has decarboxilase on it which breaks down oxalic acid (this compound stops calcium digestion which agreggates to form kidney stones). Conventional spinach only has the oxalic acid present so you have to cook it.

Screw the corporate agenda meta-studies - organics is superior.

Scuse the rant, hope that helped.

[maikeru]

Originally Posted by Getting A Life

Soil is no good as a hydro medium. it stays wet and promotes pythium and other undesirable organisms to proliferate. Many of these problem organisms are not present in hydro media. Air is critical, saturated medium systems incorporate high dissolved oxygen levels or ebb and flow designs with wet/dry cycles.

Some glomus species of mycorrhizae do well in hydro and will make a difference to your setup, glomus intraradices, glomus mossaea... so the mycogrow is a good choice.

Try a TP mix without the soil. Pottery, char, skip the bones...

If going organic you want a medium that is porous for microherd to inhabit. Hydroton, clay pottery, char, lava rock....

Yes, the swiss chards in soil are doing OK, but not great. Growth is much slower than the ideal, but they seem fat and happy. Spinach seedlings died.

Did some reading and it appears what I'm doing is termed "passive hydroponics."

Passive hydroponics - Wikipedia, the free encyclopedia

Made a second hydroponic setup with a 50/50 perlite + chunk charcoal mix, put in the same seeds, and almost all the spinach and swiss chard seedlings have come up strong, big, and healthy. Charcoal was lightly doped with Miracle Gro fertilizer before addition, so that it did not steal nutrients from the seedlings or retard their growth. Supplied each pot about one teaspoon of MycoGrow compost tea, and may add some more as the seedlings gradually grow bigger. I believe those species of Glomus are present in my MycoGrow, because they sound familiar. I can check this later on Paul Stamets's website. Hope the microbes will like living in the charcoal and perlite. It is looking more promising than my first one.

Plants in hydro can create water roots, these will convert to air roots fairly readily. however, they also develop air roots, which DO NOT convert to water roots. Water roots are those roots growing in the zone that is always submerged. Flooding above the water root line causes lysing of cells on air roots and they literally begin to rot. Upshot of this is unless you are using deep water culture or similar methods you should have a system whereby your roots are never submerged above a set level. Soaking is fine, saturation for more than a couple of minutes is not. Also, if your water roots are dried out for several minutes they become air roots, and then you flood them again - more problems.

Yes, I'm keeping water levels at only a few cm and air and oxygen flow to the roots should be high because of the porous terra cotta and perlite/charcoal mix.

Upshot is you want your water delivery system to be constant, and at consistent levels.

Wicking - yes - in soilless medium with lots of gaps for air.

Tomatoes love hydro, peppers, watercress, these are easy to grow and the watercress punches well above it's weight as a healthy food. Spinach. Did you know spinach grown organically has decarboxilase on it which breaks down oxalic acid (this compound stops calcium digestion which agreggates to form kidney stones). Conventional spinach only has the oxalic acid present so you have to cook it.

Screw the corporate agenda meta-studies - organics is superior.

Scuse the rant, hope that helped.

Super helpful rant. I love learning more about cool stuff and I tend to write long posts myself. No problem with it at all!

Yes, I'm trying to be organic as much as possible (if one will forgive the use of Miracle Gro). I'm a big fan of organic and home-grown foods now. And I believe it is ultimately more sustainable. I'm betting my future on this, so I hope I'm making the right choice.

Can you recommend any good books on hydroponics that I could pick up?

[Getting A Life]

Wish I did know some good hydro books. They all deal with chemical nutrients (one's I've seen) and to that end create an expensive to set up and expensive to run system with pollutants as a byproduct. Generally books (imo) commissioned by fertiliser salespeople.

Stamets huh. I have all 5 of his books here but have only read 2 so far as school is so demanding. His products have the correct glomus species in them. Amazing mycologist, he is one of my inspirations. Today I found some immature stinkhorn fungi that when pulled apart (look like a puffball at this point) have the whole structure of the adult fungi inside it enveloped in a type of clear gel. Like a snowglobe almost. And, when the skin is broken on them, it turns purple! NEAT!

Never seen a bruising reaction so severe in any plant, not even in those mystical fungi.

Glad to hear the char/perlite experiment is going well.

What I found with hydro over the years is that it appeared to be superior to dirt gardening till I got my soil up to scratch. Now, my hydro efforts are confined to the greenhouse and mainly off season for fresh greensherbs/tomatoes year round. It certainly does help keep my diet ship shape. This is run by recycling pond water plus some liquid seaweed.

To fix my soil I used lots of compost, lots of compost tea, seaweed, and patience. You come across to me as someone familiar with soil food web and their work with compost teas. The secret to good tea is good compost (and lots of air ie: 0.4 cfm per gallon).

Sorry, went off topic, as you can see I'm a keen dirt gardener now.

If you ask specific hydro questions I may be able to help with some of them.

[Michaelangelica]

maikeru
Some pics please?
How much did it cost you to set up?

Another good thread for our sub-forum Agriculture/horticulture/gardening/indoor plants ? Moderators and other powerful people pls note?

[Ganoderma]

personally i dinf soil to be better unless you got cash to fork out for hydro. i ran one once with tomatoes and bought the better chems, and they grew fast, but they just dont taste the same as good ol in the ground composted plants.

i saw some pretty wicked systems in malayasia growing lettuce, they used fairly standard piping with water flowing through. i believe they used small baskets filled with geolite or whatever its called...looks like round lava rock. i used that in my experiments as well (using piping) and it worked good for avoid bacteria/nasties in the roots.

the setup seems pretty easy and straightforward when you know what you want to grow, the hardest part, for me anyway, is water quality/nutrition...and ph....water here is like a lemon! once you figure out a nute solution your all green

i tried keep fish in the reservoirs, for a future experiment with aquaponics, and found that it works ok, but the plants always had deficiencies, and pretty much still needed additional chemicals which i didnt like....but i never really pursued that very far.

here are the lettuce grown there



also some strawberries they were growing via drip in coco or peat. i used this for a month with some otehr plants, and worked well but salt buildup was an issue....had to be flushed every now and then which is a pain.

[Getting A Life]

Nice - yes, the pond water needs liquid seaweed to grow things efficiently. Others swear by high populations of fish and only add chelated iron for good results. As I am not raising fish to eat the seaweed works well and the fish have plenty of room to enjoy life.

I love those strawberry stacks! That's some good space efficiency right there, and with land at such a premium is a very good way of growing in highly populated areas. Vertical gardening is starting to get a lot of press, a building being constructed now in Dubai is basically a skyscraper/garden said to be able to provide food to 27 000 people.

Unfortunately my link to this is corrupted, you might find it on google.

[maikeru]

Originally Posted by Michaelangelica

maikeru
Some pics please?
How much did it cost you to set up?

Another good thread for our sub-forum Agriculture/horticulture/gardening/indoor plants ? Moderators and other powerful people pls note?

Pics in an album:

Science Forums - maikeru's Album: Hydroponic Stuff

Hey Michaelangelica, sorry it's taken me a little while to get back to this.

Update of 2 weeks later...

Setup using potting soil: It appears after the terra cotta extracted bio-oils or some type of black oily residue from the soil that is visible on the tops of the containers and the soil microbes had time to adapt and grow, that the Swiss chard seedlings are doing much better. Growth is more what I expected and more robust. Also, there are microbial biofilms coating the sides of the terra cotta containers and plenty of cyanobacteria to be found in the water below. I am not sure which microbes are making up the biofilms, but there are at least a couple different bacterial ones and possibly some fungi that can be distinguished by different colony morphology and colors. Presumably they're from the compost tea. The thin grass-like shoots coming up are some green onion seedlings I sprouted. However, does not seem amenable for spinach. 2nd planting of spinach seeds in those two side pots failed, so that's why they're empty.

Setup using 50/50 charcoal and perlite: Has treated the spinach seedlings and germination much more favorably. I think they actually like this one. My Swiss chard in the 50/50 mix germinated well, but after several days the seedlings seemed to weaken and finally all died, leaving only the spinach seedlings going strong. Onion seedlings in the mix also failed to thrive after initial sprouting. This setup also has had compost tea added to it, and it appears that the microbial biofilms growing on the perlite and terra cotta are different. Mostly fungal ones. Dark brown residue on top of the charcoal + perlite is oxidized black tea, which was used to promote healthy germination and avoid damping off. It is not oil or something similar like in the other setup. This setup has been lightly dosed twice with Miracle-Gro fertilizer, mainly to load the charcoal.

For a few days, heat and stronger-than-usual sun stressed both setups and seemed to stunt plant growth.

I will reseed the empty pots as appropriate, based on what I've seen. Just been a bit lazy.

4 small pots = $3.20 USD
Plastic container = $1.00
Media varies, but the container of charcoal for aquariums cost me $4.00. Perlite I think was $2-3 for a big bag.

[maikeru]

Originally Posted by Getting A Life

Wish I did know some good hydro books. They all deal with chemical nutrients (one's I've seen) and to that end create an expensive to set up and expensive to run system with pollutants as a byproduct. Generally books (imo) commissioned by fertiliser salespeople.

Stamets huh. I have all 5 of his books here but have only read 2 so far as school is so demanding. His products have the correct glomus species in them. Amazing mycologist, he is one of my inspirations. Today I found some immature stinkhorn fungi that when pulled apart (look like a puffball at this point) have the whole structure of the adult fungi inside it enveloped in a type of clear gel. Like a snowglobe almost. And, when the skin is broken on them, it turns purple! NEAT!

Never seen a bruising reaction so severe in any plant, not even in those mystical fungi.

Glad to hear the char/perlite experiment is going well.

What I found with hydro over the years is that it appeared to be superior to dirt gardening till I got my soil up to scratch. Now, my hydro efforts are confined to the greenhouse and mainly off season for fresh greensherbs/tomatoes year round. It certainly does help keep my diet ship shape. This is run by recycling pond water plus some liquid seaweed.

To fix my soil I used lots of compost, lots of compost tea, seaweed, and patience. You come across to me as someone familiar with soil food web and their work with compost teas. The secret to good tea is good compost (and lots of air ie: 0.4 cfm per gallon).

Sorry, went off topic, as you can see I'm a keen dirt gardener now.

If you ask specific hydro questions I may be able to help with some of them.

Yeah, I ran across Stamets's site by accident quite a while back, but as soon as I did, I was like Neo and had a "whoa" moment. I think I'll treat myself to a big Christmas present this year, maybe get a few of his books, a few texts on how to do organic farming, orchards, and other horticulture, and a few on soil microbiology that I've found in the libraries but want for my personal use. Take pics of your discoveries and share them if you would. You're also aware that some types of fungi are bioluminescent, right?

El extraño fenómeno de los hongos que brillan en Japón | El Rincón del Misterio

Soooo cooooool.

Fungi are still something relatively new for me. I've been trying to hunt down books on mycorrhizae in the uni library, but I'm mostly coming across old stuff (monographs and texts written back in the '60s to '80s), and you know that just doesn't fly in science. Sci moves way too fast.

Just slightly familiar with the soil food web. I need and want a better understanding of it. We covered it briefly in a few of my old microbiology classes, and mostly in relation to N-fixation or antibiotics. I've gathered a little more from digging on the net, reading sites, and reading papers and what organic growers are up to. It's like I'm always getting a few new pieces of this gigantic puzzle.

Seaweed is an excellent fertilizer and soil amendment. I've made my own seaweed fertilizer before and it has surprising results. Plants love that stuff.

[Getting A Life]

Mycorrhizal fungi is a difficult field to learn about here as well. Many species have not had their fruiting bodies identified and growing them without hosts is proving nigh on impossible in many cases. Only some double as free living saprobes.

But, they are a crucial part of the picture. Big trees in the sun giving small trees in the shade carbs via a fungal bridge. A communication and transport system.

One thing I found extremely revealing was a statement made by Dr Elaine Ingham - paraphrased... "pH is determined by soil biota, not the other way round".

This statement lends the question, what does pH tell us about the inhabitants of our soil?