Custom Soil Blend Lab Results: Interpretation/opinions?

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Larry.G

Larry.G

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I recently completed my first organic soil grow and was generally happy with the results. I learned a lot but there were a few times when I ran into deficiencies and found myself guessing at solutions way too often which I think made things worse. I was using pre-mixed soil and wasn't 100% sure of the recipe.

This time around, I've pre-mixed my own soil and sent it to the lab. Received the results today but I'm a little confused on how to interpret them. All of my levels scored "Very High" on the lab's result key, so I guess that's a good thing.

Looking for your expert opinions...Any soil scientists want to take a look and offer their advice on if I need any amendments or adjusting - or am i ready to go? I'd love to hear your thoughts.

My recipe:
5.0 parts Pro-Mix BX
2.0 parts Local Leaf Compost
1.0 part Local EWC
1.0 part FoxFarm Ocean Forest
1.0 part Pumice
Added 1.5 cups/10 gal of 4-8-4 dry blend (fish bone/feather/kelp meal, rock phosphate, KMag, greensand, basalt, glacial dust)

Note: There is NO dolomite lime added to this mix - yet.

Here are the soil results:
Soil Sample Results - May 17.jpg
 
Blaze

Blaze

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Micronutrients are all too high, especially the boron. You do not want these in the 'very high' range, it will cause lock out. You wanto 'very high' in the macros like N, P, K, and Ca. Nitrogen is low in my opinion, the other macros are really high. Organic matter is way low, should be at least two to three times that.

Ditch the Foxfarm it's garbage and probably where your excess micros are coming from. They tend to use a long of filler in their junk.
 
M

Markshotrod

8
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I wouldn't say foxfarm is junk I use it with organic grow humic acid and molasses during veg then during flower I use organic bloom some molasses oh and I use sump tea once a week and stopping two weeks into flower the sump tea and I never have problems I was going to do everything you did but when it was my first grow in soil I was just thinking you know what don't overdo it it's your first time growing in soil so just keep it simple stupid LOL talking about myself and to my amazement everything came out great so I've been grown in soil the last 5 or 6 times and the hydro equipment has been parked I really like the soil good luck on your grow show pics as you go along and good luck again
 
leadsled

leadsled

GrowRU
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Balance is key. Do not want to have excess.

Not that great of a start,compost was used in excess.
Low calcium, excess Mg and K.
S and Trace minerals are in excess.
PH, Sodium and exchangeable hydrogen is not shown.

Where did you get the soil test done?
FYI< That soil does not need dolomite, Tiny bit of ag lime and then ag gypsum. Would better to start out with better proportions and lower Mg and K. Do not forget sodium.

If you want to try again and get better results. Mix the promix, ewc and aeration. Test the soil. Then add what is needed.
 
Larry.G

Larry.G

31
33
Micronutrients are all too high, especially the boron. You do not want these in the 'very high' range, it will cause lock out. You wanto 'very high' in the macros like N, P, K, and Ca. Nitrogen is low in my opinion, the other macros are really high. Organic matter is way low, should be at least two to three times that.

Ditch the Foxfarm it's garbage and probably where your excess micros are coming from. They tend to use a long of filler in their junk.

Thanks for the input. I tried to keep the recipe simple but I might have been heavy handed on the compost and dry amendment mix (along with my Ocean Forest "add-on") as well.

I thought it my OM% seemed very low, so I asked the lab to re-run the test because with 20% EWC/Compost on a peat-based mix, I'd expect the OM% to be much higher. I was shooting for 25-35% OM.

Balance is key. Do not want to have excess.

Not that great of a start,compost was used in excess.
Low calcium, excess Mg and K.
S and Trace minerals are in excess.
PH, Sodium and exchangeable hydrogen is not shown.

Where did you get the soil test done?
FYI< That soil does not need dolomite, Tiny bit of ag lime and then ag gypsum. Would better to start out with better proportions and lower Mg and K. Do not forget sodium.

If you want to try again and get better results. Mix the promix, ewc and aeration. Test the soil. Then add what is needed.

Thanks for the thoughts. I was too heavy-handed on the dry amendments and the compost. These tests are really critical, I was about to start a pretty big grow with this medium. Not now.

I had the soil test done at Spectrum Analytics and like I said above, I asked them to re-run the test because the OM% seemed low. I've added the results in a different format that include sodium numbers (thanks for that advice). Can't say enough good things about Spectrum, great guys who did great work and were very understanding.

Based on this advice and pending the results of the soil re-test, I think it's wise to start from scratch. I'm going to make a new mix at 7 parts ProMix, 2 Parts EWC, 1 Part Pumice and go from there.

Any other advice on creating a mix with high OM% that still keeps the other micro's within range?

soil_sample_re-run.jpg
 
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Larry.G

Larry.G

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Update: Spoke to the lab today, Organic Matter was tested using an alternative method and came out to 33%. Not that this changes everything, but makes more sense based on my inputs.
 
leadsled

leadsled

GrowRU
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263
I see why now, you are using spectrum.
Spectrum Lab: trace minerals will be higher and usually lower levels on Si and OM.

Comparing the first pic and then the test you posted. First test 947 Sulfur and then next report 1947 ppm. Little inconsistent.
You new mix sounds like a better base.
 
Larry.G

Larry.G

31
33
I see why now, you are using spectrum.
Spectrum Lab: trace minerals will be higher and usually lower levels on Si and OM.

Comparing the first pic and then the test you posted. First test 947 Sulfur and then next report 1947 ppm. Little inconsistent.
You new mix sounds like a better base.

Just wanted to let you all know that based on the comments above, I mixed up a fresh batch at 7:2:1 of Promix, Castings, Pumice. Sent it to Logan and here are the results:

IMG_0556.jpg


I think this gives me a much more balanced base to begin adding goodies. No compost in this mix at all (maybe trace amounts from a few handfuls of recycled soil)..

Thoughts? Am I close? :)
Larry
 
Perception

Perception

452
93
Looking a lot better! I'm still learning about soil nutrient balances though. What are the "desired values" based on? Is it a general standard, or something you provided? That 6:1 calcium/magnesium balance looks great (from what I understand it should be), although I'm curious if others will confirm this as being correct.

If you wanted to make up that deficit in a safe/low-impact way, maybe an addition of some oyster shell would help? Would probably raise the PH a little too, and then slow release the cal/mag.
 
leadsled

leadsled

GrowRU
2,145
263
Just wanted to let you all know that based on the comments above, I mixed up a fresh batch at 7:2:1 of Promix, Castings, Pumice. Sent it to Logan and here are the results:

View attachment 710142

I think this gives me a much more balanced base to begin adding goodies. No compost in this mix at all (maybe trace amounts from a few handfuls of recycled soil)..

Thoughts? Am I close? :)
Larry
Way better. Excellent! Good job on following directions. I

Will need some Ag Gypsum. Phosphorus and Manganese.
Can add some kelp and then a meal for nitrogen and phosphorus. I suggested crustacean for a source of chitin and n and p.

Here is what you can add Per yard

245 g - Kelp Meal
475 g Ag Gypsum
1406 g - Crustacean Meal (4-3-0)
827 g - CalPhos, Soft Rock Phosphate
79 g - Potassium Sulfate
54 g - Manganese Sulfate.

 
leadsled

leadsled

GrowRU
2,145
263
oops. posted too quick and unable to edit my posts.
p.s.
The ph will rise when you add the amendments. Ideally would be good to get the sodium levels lower. So can run some water through the medium after amending. Make sure the water does not contain excess sodium. Many times there can be an excess and then it builds up in the medium.

The amendments listed are a suggestions based on the test results. If you want to use a different meal. let me know and can calculate the difference.

Hope that helps!
 
leadsled

leadsled

GrowRU
2,145
263
Looking a lot better! I'm still learning about soil nutrient balances though. What are the "desired values" based on? Is it a general standard, or something you provided? That 6:1 calcium/magnesium balance looks great (from what I understand it should be), although I'm curious if others will confirm this as being correct.

If you wanted to make up that deficit in a safe/low-impact way, maybe an addition of some oyster shell would help? Would probably raise the PH a little too, and then slow release the cal/mag.
The desired values are based on the work of Albrecht. He studied the relationship between soil and human animal health for over 30 years. The ideal values also create the ideal environment for the microbiology.

Shooting for calcium to be at least at 68%, 12% Magnesium, 4% Potassium and 1.5% or less Sodium as far as cations.

Add cations will raise the ph. Not solely calcium carbonate.

Shooting for the first 60% of calcium to come from calcium carbonate. The remaining 8% to come from ag gypsum.
So not a good idea to add oyster shell at this point. Time for Ag Gypsum.

Then work on balance of microbiology. Bacteria, fungi, protists, nematodes and microarthropods!

Hope all is well.
 
Perception

Perception

452
93
The desired values are based on the work of Albrecht. He studied the relationship between soil and human animal health for over 30 years. The ideal values also create the ideal environment for the microbiology.

Shooting for calcium to be at least at 68%, 12% Magnesium, 4% Potassium and 1.5% or less Sodium as far as cations.

Add cations will raise the ph. Not solely calcium carbonate.

Shooting for the first 60% of calcium to come from calcium carbonate. The remaining 8% to come from ag gypsum.
So not a good idea to add oyster shell at this point. Time for Ag Gypsum.

Then work on balance of microbiology. Bacteria, fungi, protists, nematodes and microarthropods!

Hope all is well.

Awesome! Thanks Leadsled. I, like the original poster of this thread, am working hard to make all the pieces of the puzzle fit, but it's hard to figure out how to make all mesh.

I just read about Albrecht. Are you familiar with Charles Walters's books? I just started reading Minerals For The Genetic Code, and I highly recommend it. The foreword alone blew my mind. I think you, and anyone else on this thread, would really like.
 
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