Is there something like a plant nutrition for dummies resource? I feel like I’m kind of operating blind because of an inadequate background.
I start with a very simple mix from Bruce Bugbee. That has 50% peat moss and 50% vermiculite, plus 140 g/l of dolomite and 35 g/l of gypsum. Now I want to make some changes but not ‘break’ it. I changed half the vermiculite to perlite because I believe I want it to drain faster. That reduces the silica available to the plants, so I add 100 g/l wollastonite from some newer Bugbee videos. I don’t have access to rice hulls (the newer video has that too) though, so I leave that out and add a little more wollastonite, going from 100 g/l to 140. That seems to be working, but maybe I can do better.
Suppose I want to try something else? I see that basalt will add iron and I don’t have any of that. And Azomite has small amounts of other trace minerals I may be missing. But how much do I add?
I’ve seen lots of specific recipes around, but it’s hard to find much on the theory behind them. If I just wing it and proceed by trial and error I will waste a lot of time and material. Is there something I should study for background first?
I bet that was a wet mix before. Usually you would add vermiculite to the top few inches to hold moisture and break down amendments.
How so? There is Si in perlite but in an unavailable form. It would take years before biodegrading. Lack of time before the brittle usually turns to dust that coagulates on the bottom of the pots like concrete. You’d be better adding parboiled rice hulls for Si/aeration at 10-30% replacement of the total 1 part aeration needed.
Maybe this could help. It’s also a pet bedding material. I got mine from the feed store. Search parboiled rice hulls on amazon or eBay
Keep to ratios. You don’t wanna go adding blindly. The wollastonite is more an outdoor thing and used at lesser volume due to moisture retention. At least it doesn’t mess with the pH like vermiculite (7.5 ish).
Mineralization is what makes soil and not dirt. Most people add 3+ types of rock dust to cover what is missing in others.
Azomite stands for A-Z minerals and is pretty well standard. Very similar to Glacial or Granite dust. Bassalt or Micromite are both mineral rich, and are paramagnetic, simulating the Earth.
The list goes on: Oyster flour, Limestone, Gypsum & Calcium Phosphate (soft rock phosphate) are the rock Ca inputs Langbeinite is another rock that provides K Mg to the mix
Post your full recipe and tag me. I’ll see what’s up.
The reason I thought I was depriving the plant of silica is because I cut the vermiculite in half. The Bruce Bugbee video on maximizing plant yield says the plants are getting silica from the vermiculite. His videos are something of a moving target though as his research progresses. Later ones come mostly through hints from other people’s questions on a variety of forums. In a later one he removes most of the vermiculite and adds rice hulls and wollastonite, both of which replace silica. My recipe for my last grow was:
50% SunGro Sphagnum peat moss (this has a bit of wetting agent already)
25% Vigoro Vermiculite (this is a Home Depot brand, so easy to find)
25% Vigoro Perlite (Bugbee's recipe doesn't include this, but it drains faster for me)
140 g/l Down To Earth Dolomite Lime (straight from the original Bugbee recipe)
35 g/l Down To Earth Gypsum (again from Bugbee)
140 g/l Wollastonite (Not sure who makes this but I found it at KIS Organics). Bugbee recommends 100 g/l, but says you can leave out the rice hulls and boost the wollastonite, but doesn't say by how much.
In case it matters, I am an outdoor grower. I put this mix in 15 gallon grow bags outdoors and use autoflower seeds. I’m in Hawaii so there is lots of sun but also pests. I generally avoid compost or fish emulsions because the pests seem to like them too.
I also used Bugbee’s nutrient recommendation which is Jack’s Professional Peat Lite with a bit of potassium silicate added. But I switch to Jack’s Professional Bloom Booster for flowering.
Bugbee also recommends copper which I do not use. It’s supposed to prevent fungus but kills the beneficial ones too. I’ve been adding a bit of mycorrhizae when I uppot from a seedling cup to the grow bag and I was afraid the copper would kill it.
I don’t want to sound like I have a real problem. I’m a medicinal grower and my yield is more than enough for me, I just want to see if I can do better :). I want to make small, measured changes from here though so I don’t completely botch a grow.
I suspect, but don’t know, that I am missing trace minerals. My local grow shop now has Down To Earth MetaBasalt, which adds iron and most of the other minerals on your list. They also have Azomite which probably has the even rarer ones. There is also a rock phosphate which I was not going to add because I was afraid of duplicating the phosphate in the nutrient mix. Truthfully I would like to add the Azomite and Metabasalt but have no idea how much. I would like to become a bit more knowledgeable about this, not just get a great recipe from someone. This is far from my wheelhouse though. I never did any gardening at all before trying to grow cannabis. I have a lot to learn.
That would be a soilless base mix for the Jacks. The salts provide the micros. I’m organic, so no help to you. If you were to mineralize that base, it would be applied at 2% total volume. You should be able to find volcanic tuft. That provides Si and minerals that could be 1/3 of the combined 2% needed.
Copper fungicide? Better choices out there. Don’t go and add this to the soil. You wanna avoid heavy metals.
