passive plant killer

links added 9-17-11

ImaginaryFriend's INTERPRETATION of Delta9nxs' PASSIVE PLANT KILLERS
https://www.icmag.com/ic/showthread.php?t=189096

Zeke99's PPK index
https://www.icmag.com/ic/showpost.ph...postcount=2264




Today is tuesday, september 22. on the 18th I put a 6” clone into a device that can only be described as a “non-circulating, stagnant, hydroponic, capillary wick plus capillary medium with root sump, evapo-transpirator”. Or possibly it will be known as the “passive plant killer”. That's it, the PPK device. Sounds like a grade “b” horror flick. As I have never grown anything in it this just might turn out that way

For quite a while now I have been interested in passive growing techniques. I have been comparing containers and mediums through both my own experience and reading about the experiences of other growers. Not only those in cannabis circles but of greenhouse professionals of various descriptions. Agricultural research papers have been another invaluable resource. There is so much information out there and so little time.

The medium whose existence reveals my most glaring lack of experience is coco coir. I've pretty much been around the block with everything else. The adventures of the coco heads, over there in their own nice comfortable little forum, (i'm so happy for you folks, but I demand a turface forum), are extremely interesting to me. They have accomplished some extraordinary grows over there that should be read by anyone who grows anything.

I've tried almost all forms of active hydro with the exception of aeroponics with more or less success. Some great grows, some mediocre ones, and some dismal failures. Passive hydro in several forms starting with 2 yrs using turface in standard one gal nursery pots, 72 at a time in a plastic lined 104”x 52” 2x4 frame on the floor. Then I experienced the “hempy” phenomenon and have been trying variations on the “internal reservoir” technique ever since. These variations consisted primarily of trying different size and shape containers with different media and drain/overflow configurations and heights while using different fertilizer regimes. Not too challenging. I mean just how many ways can you pour water through a bucket? All in an effort to increase yield. Two steps forward and one step back, slowly and painfully (sob!).

I want to state right up front that I have not invented anything. Rather, I have been shamelessly stealing every idea I could find and trying to put them together into something that might work. But I think I should be rewarded for my creative manipulation of plastics and masterful use of tools. Good hash will do nicely, thank you!

This is a very cool time to be involved in growing our favorite plant. We have tens of thousands of growers doing independent research on every subject imaginable and reporting their results back to sites like this one. While not usually very scientifically conducted, we have multiple people trying the “new” ideas and reporting. If enough people say something works or doesn't work, they are probably right. There is continuous progress in both yields and potency. And more and more grow everyday.

What i'm soliciting here are any and all comments or pointers about any part of this effort. Any input or links to passive growing techniques are welcome. Anything anyone wants to show and tell is fine with me.

So, enough background and intentions and on to the Passive Plant Killer.

Just some general purpose shots with a bad camera in the hands of a bad photographer.

last

so, this is a cloner? I'm trying to understand!

clear as mud.

no fair -- Lacy LePlant is already taken....by a MILF. Welcome Nancy......

i'm with Haps.....WTF

howdy, nice to meet you all!

i intend to grow a 5' tall, 10 oz plant in it.

the clone is in the first one built and has been in since the 18th. 100% turface in the top bucket and the pvc fitting sump. plus the 2 capillary strips. the clone was about 6" above the medium on the 18th and is just under 8" today. the "res" in the 10 gal tub holds 3.66 gal at the 5 1/2" level, which is set by the overflow standpipe. the cut off support bucket is set at 6" in order to maintain a minimum 1/2" air gap, forcing capillary rise through the sump pipe while preventing any possibility of a perched water table in the grow bucket. this is desirable because the volume of space that would be occupied by otherwise drowned roots will now be available to "air" roots taking in more o2. the foam you see sandwiched between the buckets is there for multiple reasons. keep light and debris, insects etc. out of the res. the foam stops algae and slows extraneous evaporation. it will also help insulate the roots from the cold. i want all evaporation to occur through the medium.

the plant has not yet had time to get roots to the bottom so i have to top water with small amounts of nutrient solution to keep the pathway wet. the excess water runs through the medium and into the res below. as there are no roots in the res yet the excess nutrient solution sits in the bottom accumulating. it has risen almost to the top of the standpipe now and so i am able to withdraw a solution sample to check ph and tds as well as recirculating some through the medium as necessary.

we all know that cannabis is capable of altering it's root structure to some extent to adapt to various habitat. this is one tough plant with a strong will to survive.

those that grow using medium-less or nearly medium less hydro such as dwc, bio-buckets, nft, or aero have observed the plant grow a preponderance of water type roots when presented with a continuous supply of well aerated water. and at the same time show very little air root development. conversely, growers in various media, when depotting after harvest, will see a large volume of "air" type roots. especially in static or passive systems. the plant does not seem to care where it gets it's oxygen as long as it's needs are met.

this is an attempt to force the plant to develop a disproportionally large quantity of "air" roots while using a capillary material and a medium with high capillary capability plus tap roots to maintain an adequate supply of moisture and nutrient. it is my belief that the upper "air" root structure will take in enough o2 so that the tap or "water roots" don't drown.


well, that's all for now

just for shits and giggles but whered the 5 foot tall plant and 10oz? educated guess....

What or who is turdface?

Haps - HA!

Delta9 – This is going to be fun! I’ve noodled a bit on passive + wick recently and I’m glad you are leading the way. I’ve had one concern with wick systems and our favorite plant that has kept me from playing with wicks in the past. I’ve heard that wick systems sometimes fail when feeding plants that drink a lot of water over a short period (like a blooming 5 ft. tree might, especially in the summer). The wicks just can’t keep up. So I’m glad to see you are “…applying the electrodes of science to the testicles of dogma”. We’ll have an answer in 15-16 weeks I guess.

Beyond that, what nutes are you using? GH FloraNova Bloom? If so, I worry about FNB settling out in the lower runoff reservoir. Maybe a reason to use GH Flora multi-part? It would be a shame. FNB is sooo sweet.

wtf

wtf

hey, teercsimfodeswabvcdlkjhg..... here's one i whacked on the first. it's actually a little on the light side, i only got 9.35 oz. it's in a 5 gal bucket of perlite. a whole lot of water and nutes were poured though this thing over it's 16 week life span. i hope to grow a better plant with the PPK using a lot less materials. my best so far in hand watered "hempy style" containers was 11.47 oz in a 10 gal bucket of turface. in 2 more weeks i'll have the first of 10 consecutive plants that are being grown in 10 gal containers, again using perlite.

haps, haps, haps haps, tsk! tsk! "what or who is turdface?" pull out your makeup compact, sweetheart, and look in the mirror! or, it's the stage before "shitface"!

hey, cactus, how are you! if you've got anything sketched out yet put it up. i need all the ideas i can steal.

yeah, i've had large plants use more than a gallon a day. i'm hoping that by utilizing 3 methods of supply i'll be able to get enough moisture to meet peak demand.

i am using fnb on this first one at least. i figure there are so many unknowns in this that i should use something i totally understand. i,ve grown a lot of plants with it, sweet tooth #4 specifically, and will know pretty fast if it's not working.

but, i've also got on hand about 6 lbs of maxibloom, 2 gals of flora bloom and one micro, plus a couple more gals each of fnb and fng. then there's a 25 lb bag of jack's professional 15-16-17, a 25 lb bag of jack's 10-30-20, 50 lbs of greenhouse grade calcium nitrate, bottles of calcium chloride, 5 lbs potassium chloride. epsom salts. 60 lbs hi-phos bat shit, a cubic yard (heaping pickup bed) of worm shit, 25 lbs kelp meal, 2 5.5 cu ft bales of sphagnum peat, 4 4 cu ft bags of perlite, hundreds of ruined containers that i've drilled all kinds of weird holes in and are now useless, neem oil, hydrogen peroxide, pyrethrum bombs, a compass, and a magnifying glass in case i have to start a fire. did i mention 4000 lbs of turface? oh, yeah, and a pissed off wife.

Geez. Don't have the nute collection, but I do have a pissed off wife...

You asked for it. Here’s what I’ve been thinking recently regarding passive, wicks, and such. First where I’m coming from. My two favorite methods of growing are totally passive Hempy-style and Nimby-style DWC.

Nimby was an OG mentor who refined a simple DWC approach with an aquarium-type recirculation pump in the reservoir/root zone instead of a bubbler, a float-valve for RO water makeup, and pre-set nutes added once a week. No TDS or pH measurement, and no res changes throughout the grow. I like it because it is effective, simple to build, easy to maintain, and I can leave it for long periods unattended if need be.

I like Hempy because it is effective and bulletproof. Unfortunately it lacks the feature of un-attended operation over extended periods (I’m often out of town for 7-10 days at a time). To solve this, when I travel I add an every-other-day drip system, but to make sure I water adequately without monitoring, I have to set it so that it produces excessive runoff.

This is my attempt to combine the best features of each. Basically it’s a Nimby reservoir without the roots, feeding a Hempy through wicks (OK, it’s not a Hempy if it has wicks, but I won’t go there). By moving the roots out of the reservoir and into the very “airy” perlite medium, I hope to avoid potential root suffocation risks due to poor water circulation in thick root zones and summer overheating. Also, there is no Hempy runoff to deal with.

OK – It is not totally passive, but I think it addresses my specific issues with minimum complications. Either the recirculation pump or the float valve, or both, can fail and the system will still limp along for a week till I can get home to fix it.

The attached sketch shows what it looks like. I use low profile Sterilite bins because I SCROG and try to minimize overall height. Also I like using little aquarium pumps to keep the nutes mixed instead of bubblers since they are completely silent.

You still did not say what turface is? I have never heard of it, so I ask.

i'm sorry, haps,

i'm sorry, haps,

i thought that was all just play.

turface is the trade name of an arcillite clay product marketed by the profile co. it is calcined, which means it has been kiln fired, in this case to 1300*, which turns it into a permanent ceramic. it is then ground into 2-5 mm pieces or about the size of coarse perlite. it is used primarily as a soil conditioner to break up compacted soil. golf courses use a lot of it. it's the red stuff on baseball diamonds and running tracks. it will almost retain it's own weight in water yet still have nearly equal air pore space. it has a cation exchange capacity of between 31 and 41 meq./100g, which gives it good buffering qualities. it has a ph of around 6.2. holds plants up really well and is infinitely re-usable. all of mine is between 4 and 7 years old and has been used many times.

turface mvp is the coarse grade most desirable for our uses. i screened all mine with a standard mesh aluminum window screen to eliminate dust and fines. then i wash the hell out of it.

the same exact thing is sold at wally's, lowes, and home de pot as schultz aquatic potting soil at 8 bucks a 10 lb bag (8 liters), but i get mine at a landscape and turf supply for 9 dollars per 50 lbs. the only difference i can tell is that the schultz product is designed for use in planted aquaria and comes pre-screened for fines and washed. you will lose about 30% of original volume by screening but it gives you a lot more pore space per volume.

well, haps, i hope i have adequately answered your question and i'm sorry for the misunderstanding. later

hey cactus

hey cactus

nice graphics, i need to get something to draw with.

oh, btw, to everyone, i don't care if it's passive or not,or on topic or not. the only thing that matters is that we have a good time and use this thread as a learning experience. i like to laugh and play. show me yours and i'll show you mine. lets talk about it.

i'm going to try to keep the PPK free of electric appliances, but if you are going to use a pump anyway i see a way to try something that might act like a supercharger.

by aquarium pump i assume you mean one of the magnetically driven powerheads. if so, most of them have an input for an air line that pulls air into the stream via the venturi effect. so you could move water around and put a little fresh air into the res.

if your containers fit together tightly or could be made to fit tightly, with minimum air leaks you could move a significant amount of moist air up into the root zone through fittings like the one i built for the PPK. except maybe 1/2" ones with a little screen to prevent your medium from falling through and stop large roots. some air would probably also make it upstairs through the wick openings. not much, just a slow, steady movement.

you depict an air gap above your solution. almost everything i've read says this is desirable to prevent a perched water table from blocking air flow and occupying valuable air root space.

also, no matter what you do you are going to get some roots in the res. if the wicks can go up the roots can go down. i get roots intertwined with wick material in my cloners every time.

the float valve is a nice touch. constant small corrections often are better than large ones far apart. less opportunity for ph to get whacked and less stress on the plants. also, it gets you time away.

i see where you are thinking about 100% perlite. you are probably aware that i'm the process of switching back over to turface. i've been growing a plant a week in perlite for 8 mos and have 10 weeks of them left. you might say i've been able to get familiar with the substance. while i grew some nice plants in it i had a constant battle with ph in 100% perlite. perlite has virtually no cec and so has little buffering ability when used alone in passive. in the greenhouse tomato industry it is used alone frequently but on drip apparatus. apparently the constant flow through mediates the tendency for large ph swings. perlite is a great medium when used with something with a significant cec, such as turface, vermiculite, coco coir, or peat.

Later for now

Thanks for the info, nice to learn something new. Good luck with your design.

Delta9 - Thanks and much respect for the input. So much to learn and so many idea to try! Your suggestion of a pressurized res pushing moist air up into the root zone is intriguing. I’ve become a bit of a nut recently trying to maximize oxygen diffusion to the roots since I see it as the key to healthy plants and rapid growth. It’s the primary reason I’ve been drifting toward perlite. It just seems so “airy”. However, when I look at the data, turface is arguably superior.

I’ve used turface with great success for the last two years, ever since I followed your lead and gave it better drainage. So now I’m torn between trying something new or sticking with the old reliable. What you say about 100% perlite’s tendencies toward pH swing worries me a bit. Had my share of that with DWC till I got things dialed in.

What intrigues me most about your PPK and similar approaches is the elimination of runoff. It goes against everything I “know”, but the more I look around the more I see evidence that I might get through a flower cycle without having to worry about salt buildup due to lack of flushing, as long as I am careful not to flood the rootzone for any significant length of time. In fact, on my last couple turface grows, I watered slowly till I first saw runoff, then I plugged my runoff line (at the very bottom of the bucket – no res volume). I’d allow a couple hours for the turface to evenly absorb the water and then unplug the line. No further runoff occurred, so I was operating with essentially zero runoff.

hey, here is a little experiment done by a home gardener. it's pretty well done. i just wish he had included coco.

http://forums.gardenweb.com/forums/load/cacti/msg1219545027416.html

and this is fascinating.

http://www.ctahr.hawaii.edu/oc/freepubs/pdf/HG-44.pdf

Good stuff in both references, but the Hawaii paper… ho-lee-cr@p! What a find for guerrilla growers. Interesting how healthy the roots look, even far above the water line where they clearly have been exposed for several weeks. Also note that it looks like there are air roots forming and extending horizontally. It must stay pretty humid inside the trashcan. I wonder how growth would compare in a similar volume container that is shorter with larger diameter, like a wading pool perhaps?

one key of no run-off/never dumping res, is addition of humates (humic acid). want solution to be chelated, buffered, & ph stable.

good luck delta9nxs. you will have great results.

always place a braids of the rope/wick a) directly under root mass; b) laterally; touching inner-walls of container; & c) below 2" line in container.

the roots of the plants grow into/inter-twine w/ the ropes. this is how bottom-feeding is later facilitated & permits more oxygen to be present in the media.

pure perlite too, w/ wick.

enjoy your garden!