soil aeration questions
- Thread starter im4satori
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im4satori
Well-Known Member
the pine bark must be very acidic
it along with a small amount of peat really dropped the ph a good bit...some readings as low as 5.5
so I turned the soil again and added another 5oz oyster shell per cubic ft (on top of the original 3 oz per cubic cft)
I also added 3/4 cup green sand per cubic ft
it along with a small amount of peat really dropped the ph a good bit...some readings as low as 5.5
so I turned the soil again and added another 5oz oyster shell per cubic ft (on top of the original 3 oz per cubic cft)
I also added 3/4 cup green sand per cubic ft
Pine bark is acidic, yes. Very? IDKTBH
But what really took me by surprise was the soil test on Premier peat moss that MistaRasta had done and posted elsewhere.
I've always figured Premier at ~5.5 or a bit lower. The soil test showed it to be 4.5 IIRC. That's 100x more acidic than 5.5.
Because of that AND the pine bark, I have bumper the dolo up to a full 1 1/2cups/cf.
That 1cup/cf isn't a hard and fast "rule", but more of a suggested starting point. You've seen it isn't really enough and bumped yours up. Finding out the peat moss is way more acidic than I though along with however acidic the pine bark is was enough to get me to increase my lime by half.
When the new mix finishes cooking I'll do a slurry test and see where the 1 1/2 cup amount puts me. IDK about oyster shell flour, no experience with it. Pretty much, just dolomite.
Bugeye
Well-Known Member
Get it cooking, ph will probably be where you want it in a month. If it isn't trending that way in a week, add some more lime. Maybe drop a tea.
im4satori
Well-Known Member
im also beginning to wonder if oyster shell requirements are higher than that of dolomite to be equally as effective
for example
1.5 cups dolomite might buffer acidity to an equal amount as 2 cups oyster shell to the same 1 cubic ft
I used dolomite on the first build so I decided to use 100% oyster shell this time and see if it loosen the soil more
plus my oyster shell looks less like flour and more like crushed shells so it might take a little longer to break down
but there should be plenty of lime in it now so its just a matter of time
im4satori
Well-Known Member
its funny
I feel like a got a small fortune invested in dirt..lol
im looking at it like its gold lmao
I find myself thinking my about soil structure more than I do about the plants themselves
im really really happy with the choice to switch to organic soil from hydro
real happy!
I feel like a got a small fortune invested in dirt..lol
im looking at it like its gold lmao
I find myself thinking my about soil structure more than I do about the plants themselves
im really really happy with the choice to switch to organic soil from hydro
real happy!
Buba Blend
Well-Known Member
@Wetdog
I'd be curious what your slurry test would be at 10 days of cooking, at 10 days the ph of my slurry test was 7 shown below on the right using 1 1/2 cups of dolomite lime in a 30 gallon mix.
@im4satori
What you just said about the oyster shell was exactly what I was going to ask you.
When you had a low PH, last soil batch, was that made with oyster shell or DL?
My 1st mix, 30 gallons of soil with 1 1/2 cups DL held a PH 7 throughout my last grow. It was suggested my PH was to high, might be IDK, but my plants were happy in it from what I could tell.
This mix my PH tested 7 or green as shown below at 10 days.
Slurry tests of my unamended ffof new or used are consistently the yellow color below.
Slurry test of my amended ffof always come up green as shown on the right.
Do you have the PH drops? I know you have the probe. I would be curious how the slurry test of your soil compared to the probe results.
I'd be curious what your slurry test would be at 10 days of cooking, at 10 days the ph of my slurry test was 7 shown below on the right using 1 1/2 cups of dolomite lime in a 30 gallon mix.
@im4satori
What you just said about the oyster shell was exactly what I was going to ask you.
When you had a low PH, last soil batch, was that made with oyster shell or DL?
My 1st mix, 30 gallons of soil with 1 1/2 cups DL held a PH 7 throughout my last grow. It was suggested my PH was to high, might be IDK, but my plants were happy in it from what I could tell.
This mix my PH tested 7 or green as shown below at 10 days.
Slurry tests of my unamended ffof new or used are consistently the yellow color below.
Slurry test of my amended ffof always come up green as shown on the right.
Do you have the PH drops? I know you have the probe. I would be curious how the slurry test of your soil compared to the probe results.
im4satori
Mesh size is everything with liming agents (mesh size = how finely the material is ground/pulverized)
I mean there are limestone structures dating back over several thousand years (BC era, Rome), and oyster shell mounds in Fl dated to at least 3,000 years old. It's not something that melts in the rain.
If your oyster shell is much more coarse than baking flour it could be years before it has any effect.
The mesh size should be on the back of the bag.
That amount of greensand is fine. It's gotten so expensive here what I do now is add it to my worm bins, mainly to get it started breaking down and it gets added to the mix when I top dress with VC.
Mesh size is everything with liming agents (mesh size = how finely the material is ground/pulverized)
I mean there are limestone structures dating back over several thousand years (BC era, Rome), and oyster shell mounds in Fl dated to at least 3,000 years old. It's not something that melts in the rain.
If your oyster shell is much more coarse than baking flour it could be years before it has any effect.
The mesh size should be on the back of the bag.
That amount of greensand is fine. It's gotten so expensive here what I do now is add it to my worm bins, mainly to get it started breaking down and it gets added to the mix when I top dress with VC.
im4satori
Well-Known Member
hmmmmm
this brings me to an interesting and maybe slightly confusing issue
if the chuncky oyster shell takes forever to break down
but ive already added a generous portion, how should I proceed
I don't want to end up with my ph to alkaline either
re-cap and very specific
i took what was about 16 gallons of 1x used coats mix 1/3 peat, perlite, compost
originally limed with 2/3 dolomite 1/3 oyster shell
the mix was ph 7.0 at the start
then I added (with the purpose of making the original coats mix more aerated/looser)
0 compost
3 gallons biochar
1 gallon pine bark
1 gallon peat
1 gallon perlite
2 cups oyster shell
2 cups green sand (first time addition)
2 cups gypsum (first time addition)
10 oz feather meal (first time addition)
5oz bone meal (first time addition)
1 cup mix
mix is
2part kelp
2part alfalfa
1part crab
1part neem
1part fish meal
and I wet it with a couple gallons of fish emulsion at 1 oz per gallon (fucking stinks)
I will likely soak it one more time before I use it with a basic tea to accelerate the decomp
if you add the feather meal, bone meal, and mix together, that's a total of almost 3 cups over whats almost a finished 3 cubic ft....and that's about 1 gallon biochar per cubic foot
all said and done the ph now reads between 5.5 and 6.2 (down from 7.0 starting) depending on the pot
ive only been cooked a few days
should I add some dolomite?? if yes how much? maybe 3 oz per cubic ft?
will adding the dolomite after ive already added that hefty portion of oyster shell eventually swing my ph up to high
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im4satori
Well-Known Member
keeping in mind
by the time I added all that what started out as roughly 15 gallons ended up growing to almost 3 cubic ft
so that divides the additions by 3 to get to the per cubic ft amounts
for example the 3 gallons biochar ends up being 1 gallon per cubic ft and the 1 gallon pine bark only 1/3 gallon per cubic ft
by the time I added all that what started out as roughly 15 gallons ended up growing to almost 3 cubic ft
so that divides the additions by 3 to get to the per cubic ft amounts
for example the 3 gallons biochar ends up being 1 gallon per cubic ft and the 1 gallon pine bark only 1/3 gallon per cubic ft
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im4satori
Well-Known Member
remind me
how do you do your slurry test?
if my memory serves I think its like 1/4 soil 3/4 distilled water and a few drops ???
how much soil compared to distilled water and how many drops?
Id like to compare it to my cheap meter/probe
Buba Blend
Well-Known Member
I did two tests just now with two different amounts, the soil line is were the magic marker line is on the cup. Both tests after 15 mins are pretty much the same. Usually I get two heaping tsps of soil and just pour about 2 parts water to 1 part soil.
Stir once in between, pour water into tubes and add 4 drops. The orange color test is my distilled water. It always has been that color.
Make sure the tubes and any cups or glasses are clean. I wipe them out with distilled water and dry the tubes with a twisted paper towel. Remember that dish detergent will destroy results.
Results are of my cooking soil, it was the yellow color shown in the picture above when it was unamended ffof.
Result is cloudy because I rushed but color is the same as previous test above.
You can use RO water also, I prefer distilled.
Stir once in between, pour water into tubes and add 4 drops. The orange color test is my distilled water. It always has been that color.
Make sure the tubes and any cups or glasses are clean. I wipe them out with distilled water and dry the tubes with a twisted paper towel. Remember that dish detergent will destroy results.
Results are of my cooking soil, it was the yellow color shown in the picture above when it was unamended ffof.
Result is cloudy because I rushed but color is the same as previous test above.
You can use RO water also, I prefer distilled.
@im4satori
AFA the 'chunky' oyster shell, if it's the 'chicken scratch' stuff like I tried, I totally disregarded it when adding the dolomite lime. I had added some to my worm bedding and was still finding chunks that looked like freshly added over 3 years later. I always add some old bedding to new bins to inoculate the fresh bedding.
Pretend it's not even in there when figuring your lime amount. The mix will more than likely be totally degraded (3 - 4 years), before it even starts to have an effect on pH. It's pretty much a non issue.
AFA the 'chunky' oyster shell, if it's the 'chicken scratch' stuff like I tried, I totally disregarded it when adding the dolomite lime. I had added some to my worm bedding and was still finding chunks that looked like freshly added over 3 years later. I always add some old bedding to new bins to inoculate the fresh bedding.
Pretend it's not even in there when figuring your lime amount. The mix will more than likely be totally degraded (3 - 4 years), before it even starts to have an effect on pH. It's pretty much a non issue.
im4satori
Well-Known Member
because i dont have distilled water on hand so I took 2 samples from the same pot
ph probe of this pot reads 6.0 in about 15 minutes but if the probe is left in the soil for an extended period itll eventually drop to 5.5
I added 1/4 cup soil with 1/2 cup water for each sample
for one sample I used well water from the faucet starting ph 7.5
for the second sample I used filtered spring water from the store starting ph 6.0
the sample diluted in well water reads ph 6.5
the sample diluted in spring water reads 6.0
so it would seem as though this ph meter/probe is reading low???
how reliable would you consider this slurry test?
Buba Blend
Well-Known Member
IDK, I think it would have a lot to do with the ppms of each water.
im4satori
Well-Known Member
I don't see how the ppm of the water would affect the ph readings
it should be irrelevant
Buba Blend
Well-Known Member
Careful, the spring water from the store may have added ingredients.
Buba Blend
Well-Known Member
My tap is 500 ppms and is heavy in calcium giving it a high PH. It has an affect. I can't use my tap to get an accurate reading.
Buba Blend
Well-Known Member
I think it is the low ppms in distilled water that make it useful to the slurry test and allows the ph to drift into the soils range. IDK.