Experiments Update
I've got a few different experiments going right now so I thought I'd make an update post on them.
Sip #1 (Gravel Bed) vs. SIP#2 (Cave Structure)
This one will have to be redone down the road given the N deficiency in #1. But, both plants look great, with #2 actually looking better than the other, but #1 had an 'N' deficiency for 3 weeks before I found a solution so I'm sure that set it back a bit.
#1 has much more in the way of roots in the reservoir, but that seems to just be because of how the container was built. It also ran out of gas in terms of nutrients about 3 weeks earlier than #2. Put another way, #2 went about 25% longer before starting to show deficiencies. What's interesting about that is that #2 has about 25% more soil in the container because of the way it was constructed. Coincidence or causative? I'd bet the latter as that would fit more into what experienced organic growers all say, which is the larger the container the better since a small container can't contain enough nutrients to last a whole grow.
I'll be flowering them next and will likely do another round with those same containers after they finish flowering. But I've been very impressed with both structures.
Water and Fertilize ONLY through the Reservoir
Fail. The plants only went so far/long before showing deficiencies and adding my extract fertilizers to the reservoir water did not seem to make any difference. Adding a top dress of worm castings
has improved things after about a week or so, so I'll be top dressing and fertigating from the top weekly until I get a better handle on how to keep them happy.
So, whether it is a case of two different types of roots as I had earlier postulated, or maybe something else like
@ReservoirDog suggested, either way I think I'll be watering with plain water through the reservoir going forward. And, since there is no need to worry about microbes in the reservoir, regular tap water should be fine if I run out of rain water.
ResDog pointed out that commercial products using this bottom watering approach strongly recommend mineral salts be added to the reservoir water to fertilize the plants. So maybe the KNF and Jadam Liquid nutes are just not able to be used directly without some sort of carrying agent. The Natural Farming extracts are supposed to be highly plant available, but maybe that's in the presence of something else like microbes or salts, etc. I had the same poor results using my extracts to try to run a Hempy grow. But, since I don't want to add salts to the mix, I'll have to find an alternative method to deliver the goods. Top feeding it is.
RWC as a fix for 'N' deficiency
This one looks like a success. Once I added the castings as a topdress, it took about 3 days to start to see better color and it's been about a week and the plants are definitely looking better although not fully back to all nice healthy green yet. I had tried my various extractions including FAA (fish amino acid) in the reservoir to no avail, and even started top feeding them, but the biggest improvement came when I added a fresh layer of castings to the top and covered that with leaf mold. So going forward I'll plan to topdress with the castings at least every couple of months if not sooner. That actually should work out great since that would be about the time I'd normally up-pot anyway before promoting a plant to flower. It got a bit extended this round because I am trying some pollen chucking in the flower box and I didn't want to comingle these plants with the others I'm trying to fertilize. But I'm glad it did since that gave me the push to solve the N problem.
But that brings up a very interesting question I know most of you are thinking about even though no-one has verbalized it yet which is
"So, Azi, what is it about the worm castings that work so well? Is it the great nutrients contained in the castings themselves, or is it more about the microbes they add, or maybe some combination?" Those are really good questions and I plan an experiment to find out. Once I get the seeding experiment concluded and some plants promoted into flower I'll have some veg cab space that I can use to try a few things out.
SIP Cloner
This one is a work in progress. Plants root better without water in the reservoir because that keeps the soil too moist. I like the structure of being able to root plants directly in a small SIP container which would eliminate an up-pot but I haven't had great success with this method, at least not yet.
Bland Soil, SIP vs Regular Pot
As more and more roots reach the reservoir the SIP plant is starting to pull away from the regular container plant in terms of performance, but it is not a dramatic difference at least yet. It does, however, demonstrate the value of the reservoir structure as being beneficial. Still, it seems the combination of the reservoir and the improved soil is what has contributed to the dramatic improvement I've seen with all of the plants I've concerted over.
Directly Seeded SIP
Total homerun. The seedling didn't have to take any time at all to convert soil roots to water roots (if that is what happens). As soon as the tap root from the seed hit the reservoir it took off. This is easily the best plant from seed I've ever grown both in speed and health. I grow mostly from clones, but I will use this method for most seeds I grow in the future.
Training with Fishing Weights (rather than ties)
I'm quite happy with Hafta's approach to structuring the plant. His CST (Constant Stress Training) appears to be quite good. I'm mainly using the fishing weights part of his approach, but am also trying to remember to pluck a leaf or three each day. I'm growing indoors in a small cabinet so I don't get a lot of benefit for the limbs swaying in the breeze but I get some as I take the plants in and out-of the cabinet.
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I think that's most of what I'm experimenting with, and so far it's been very worthwhile. The results of these tests have changed significantly the way I grow and I think I am mostly thru my transition to using what I have learned.
The new seedling is the first plant to benefit from many of the lessons so I'm going to try to run that one straight thru without any experimental detours and see how it goes. I just topped it to start training it out in a quadline because I think I'll have enough room to shape it once the two original SIP's get promoted to flower in another week or two. It may end up being too big and I'll have to resort to manifolding plants in the future given the real estate I'm working with, but that would be a nice "problem" to have.