First grow - starting medium, soil mix & organic PH?

Thanks to some suggestions from SpicySativa and May11th on my first thread i've made some additional purchases to improve my soils quality.

Thankfully what i used originally wasn't the heavy top soil i mistakenly asked for, what was loaded into my trunk was an "All purpose potting soil". It specifies that you need to start feeding after two weeks on the bag, and i've flushed it heavily already messing with ph.

After adding roughly 35% vermiculite and 1tbsper gallon of lime to that mix, I made my first post and was told not having any kind of humus was a no no. With my extremely limited selection i was able to track down 2 bags of worm castings, some more vermiculite and some peat to lower the ph slightly (after all of the flushing the soil seemed to be at a ph just above 7(more on that later).

To approx. 18 gallons of the above mix I added roughly 4gallons of earthworm castings, 2 1/2 gallons of peat, 2 5l bags of vermiculite and another 2 tbs of lime. Obviously this wouldn't sustain a plant on its own, but i will be using the general organics go box.
does it sound like i've made enough amendments to create a healthy microherd, and by proxy, a healthy garden?
Would this mix be ok to start a seed in or would the castings burn it?

I haven't had a chance to do a run off test on the new mix but i will try to get it as close to 6.5-6.8 as i can, however im a little confused by all the "Don't worry about ph, your soil and micro do the buffering" Does this mean the bacteria will naturally adjust my soils ph or secrete the nutrients at a suitable ph for the plant? Or does it just mean as long as you have a proper ratio of lime and peat to get your soil in the ideal range, you don't have to worry about the feed solutions ph dropping to 4 when you add your nutes?

One last question regarding ph, if with the seasons my tap water fluctuates from 7, to 6 or to 8, could i use small amounts of general hydroponics ph up & down for normal waterings, or do those chemicals is such small amounts actually kill off your herd??

edit:
I also upgraded to 5gal smartpots (being shipped as we speak), ordered a few bags of xtreme gardening mykos and ditched the several plants per pot idea.

Hey man, It sounds like your on the right track. Since your mixing your own soil, you will have to make sure it starts at a proper PH. Which it sounds like your doing.

I think when people say dont worry about your soil PH. They're speaking specifically to pre-mixed, store bought dirt. like fox farm, or roots organics. Yes, with those soil lines, you really don't need to monitor your PH. certain nute lines, and hard water can be variables to this "rule of thumb". As well as overwatering, and just straight up killing your dirt.

I do think though, that If you let your mix properly cook before using it. and have a good runoff ph afterwards. You really shouldn't need to monitor it from there on out. Like you said, the bacteria will naturally adjust the soil ph to their liking. assuming your water isn't ridiculously hard, and the bacteria are still alive.

If your using RO water. It takes almost nothing to adjust the PH. My RO water comes out @ around 9ph. I add calmag, and nutes. and it's down to around 5-6. I water with that no problem, I've never measured a runoff of anything other than 6.8

me personally, I would avoid putting ph up or down into your organic dirt. But I guess it depends on its source. If your mix had the proper balance of peat/lime, and your soil is good and alive, I wouldn't mess with the ph of the water/nutes going in. You really shouldn't need to. But again, Hardwater will be your enemy here.

I hope that helps a little.

ugh, don't use GH anything.

What your saying goes for both slightly acidic as well as slightly alkaline?
I dont have a ppm meter at the moment but my tap water is almost exactly 7, but i've heard it can go up to nearly 8 at different times. Lime neutralizes acids but to my knowledge not bases, so i would think it would be treated differently.

How would high ppm affect me exactly?

And yes you were very helpful, the one big one im still worried about is whether or not that mix would be gentle enough for a freshly germinated seed.

edit:
also, does anyone have any links to a thread breaking down exactly what the soil bacteria does(beyond the basics of processing decaying matter for nutes), hopefully referencing how they regulate ph. Understanding the processes will help silence any lingering doubts i have, and lessen the number of novel sized posts i force you folks to read.

no the lime will only help to raise ph. If you need to lower the ph, you need more organic material. like compost, or peatmoss. Again, if you water is decent, and your mix seems to sustain a proper ph of 6.8 after cooking for a bit, I wouldn't worry about it. Maybe monitor it late in flowering, But the lime should keep it from dropping even then.

How would high ppm affect me exactly?

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I don't think a high ppm effects you necessarily. But take my situation for instance. My tap water comes out around 9ph and 450ppm. That's 450ppm of city regulated minerals,chlorine, flouride, etc, etc, not to mention whatever else gets in from the pipes/plumbing.

If your feeding schedule calls for let's say 800pm. But your water already starts out with 400ppm (of shit). You really only get to add half of what you want to add. without burning the plants (assuming they burn at 800pm+) this is all hypothetical. which is garbage, half of your nutes are good, and half are from the city.

Now, take that 450ppm tap water at 9ph, add nutes, and now the ph is at 8.5. wtf. It takes more to adjust the ph of hard water. So the water started this way, and it's trickling down into every aspect. your soil will have a tough time bringing that down to 6.8

If your water was Reverse osmosis water. It starts at <15ppm. mine comes out aroun 9ph. It takes soooooo little to change the ph. So I get to add all 800ppm of the nutes I want, and it's all beneficial without all that other excess bullshit, my ph drops to 5-6 after nutes, and the second it hits the dirt, it seems it's at 6.8ph.

I suppose it has to do with the buffering capabilities of your soil, and how easily buffered the minerals are in either the city's tapwater/minerals, or that nice bottle of expensive nutes you bought at your local hydro store.

I dont have much time so ill have to come back later. Id say to not plant a young plant in there.

Ph can be lowered organically w molasses. It will lower it .

As for bacteria, im no master on that but I would suggest reading a book called teaming w microbes.

For seedlings you could could dilute that soil down and be okay. Make it for like 1/4 strength and you should have no issue.

You only really need to be concerned if your final irrigation solution consistently has a high pH, after everything if anything is added to it. As mentioned a lot of products and things like blackstrap molasses ultimately lower the pH of the water. Furthermore, the plant will influence the pH of the soil and also organisms in the soil, as fungi produce organic acids and tend to favor more acidic environments.

For natural ph adjustment look into earth juice natural ph up or down or just molasses for ph down, I hardly use ph up . I hate the cold, its damn near 10 degrees here.

May11th said:

For seedlings you could could dilute that soil down and be okay. Make it for like 1/4 strength and you should have no issue.

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Do you mean take about 1/4 of that mix and dilute it with equal parts peat and topsoil, or would one or the other be a better option?
I was under the impression castings were fairly gentle, could they be transplanted to the regular mix once they have their first full set of leaves, or is a veg pot necessary? (im terrified of transplanting haha)

As far as that book goes thanks a lot, $20 on amazon.ca with free 2 day shipping, its on its way.

Its just hard saying how hot the soil is. You could run 25% topsoil /25% earthworm casting/ 25 perlite and 25 vermiculite. Allow roots to grow fast and get tons of air. Should have no need to feed, just water.

Then tranplant after 2 or so weeks into larger container. I usually start out in qrt, move to a one gallon for about 2-4 weeks then they go into 3 gals for another 2-4 weeks then right before flowering they go into 7-20 gal. I run a comparison w 2 exact phenos , same soil, one in 3 gal and one in 5, the 3 gal is 30-50% less on bud mass and nearly 6 inches shorter and a ton less in diameter, smaller stems, so no more small containers for me. I like to veg for 2+ months and then flower them till I feel they are done, usually 8-12 weeks.

I've just gone through all the amendments in my mind and i think i've come up with a more or less correct breakdown of my soil percentages.

10-12gal or 43-45% "High quality all purpose fibrous potting soil" containing vermiculite (indicates feedings are needed after 2 weeks and its already been through a 3-1 flush)
8-10gal or 32-35% vermiculite
4gal or 14-15% castings (Doh....i just added 4g to the existing 18g, i didn't factor in the extra verm and peat i was adding)
2 1/2gal or 9-10% peat

Those guesses are rougher than id like, mainly because when i started i thought all i had to worry about was ph, so i didnt keep exact records.
Those numbers aren't too far off from reality, and what you suggested, so would adding a small amount of verm or perlite to the seedlings pots suffice?
Now that i've made it very slightly easier to read, does it sound good enough for adult plants, baring in mind the only reason im using castings is for the micro, i have the full general organics line, mykos and some blackstrap ready to go.

edit: would coco pellets any good as a substitute for a starting medium? I can get 60 for $12, and it'll cost me that or more to buy another few bags of vermiculite.

I dont quite know what a coco pellet is? That soil actually might not be to hot after I see how you broke it down. I think you will be okay.