Grow Mediums Peat vs Coco

[KIS]

If you are growing organically, then I think peat moss makes the most sense. If you're using a nutrient line, then I'd suggest coco coir. Here's an article I put together a while ago on the subject and just wanted to share.

This can be a hotly debated topic among growers as to what's the best media for growing plants. In this article, I'll weigh in with my opinion on the subject as there are Pros and Cons to both.

"Sphagnum" is a genus of approximately 120 different species of mosses known as "peat moss." Sphagnum and the peat formed from it do not decay readily because of the phenolic compounds embedded in the moss's cell walls. Peat moss can also acidify its surroundings by taking up cations, such as calcium, magnesium, and potassium, and releasing hydrogen ions. Under the right conditions, peat can accumulate to a depth of many yards. These bogs are slowly building and 80% of the peat moss used in the United States comes from Canada. Approximately .02 percent of the 270 million acres (422,000 square miles) of Canadian peat bog are used for peat moss mining. There are some efforts made to restore peat bogs after peat mining. It is debated as to whether the peat bogs can be restored to their pre-mining condition and how long the process takes. Many peat companies claim this to be a sustainable practice, but that is hotly debated topic depending on where you source your information on the subject.

Pros of Peat Moss:

• Free of weed seeds, pests and pathogens.
• Can absorb up to 20 times its weight in water.
• Contains beneficial microorganisms.
• Acidic pH (a "pro" in my opinion because you can add highly alkaline amendments to it).
• Contains a variety of elements, especially sulfur, which helps with proper terpene expression.
• Excellent habitat for beneficial microorganisms.
• Harvested in North America, which reduces the fossil fuel impact to get it to the United States.
• Holds 10x to 20x its dry weight in water.
• Better C:N ratio than coco coir.
• Cation exchange capacity (CEC) of 100-200.

Cons of Peat Moss:

• Depletes peat bogs, which requires them to be re-built or sustainably harvested.
• Naturally hydrophobic, meaning if allowed to dry out it will be slow to accept water.
• Needs to be kept evenly moist for optimal plant growth and health.
• Requires hydrating before use.

Coco coir is the natural fibrous material found between the hard, internal shell and the outer coat of a coconut. It is treated before use as a growth medium for plants or fungi by soaking in a calcium buffering solution; most coir sold for growing purposes is pre-treated. Once any remaining salts have been leached out of the coir pith, it and the coir bark become suitable substrates for growing plants.

Pros of Coco Coir:

• Coir pH usually runs 6 – 6.7.
• "Renewable" resource - byproduct of the coconut industry.
• Easier to rewet than peat moss, is not hydrophobic.
• Usually cheaper than peat moss.
• Different reports list coco as having a water capacity ranging from 8x to 30x it's own weight.
• Excellent habitat for microorganisms.
• Free of weed seeds, pests, and pathogens.
• Breaks down slower than peat due to high lignin content.
• Cation Exchange Capacity of 40-60.

Cons of Coco Coir:

• High salinity unless properly washed.
• Quality can vary depending on batch and source of material.
• Higher fossil fuel cost to get the coir to the United States from tropical regions.
• Does not contain many trace elements.
• Does not contain microorganisms.
• Traditionally high in sodium and potassium which can lead to calcium or magnesium deficiencies unless properly treated.
• Requires hydrating before use.
• Increased incidence of nasobronchial allergy among workers in this industry due to the high amount of dust created.
• Some coco coir in tropical regions is being sprayed with pesticides like neonicotinoids, one of the pesticides most commonly linked to honey bee death.

As you can see, it's not a black and white decision as to which growing media is superior. Personally, I prefer sphagnum peat moss because of the existing microbiology and the fact the pH is acidic, allowing for highly alkaline amendments like biochar and calcium in the form of ag lime and oyster shell flour. I've also had issues in the past with quality control on coco coir and heard horror stories of variability between batches from the same manufacturer containing high salinity. Regardless of what you choose, you'll most likely want to amend the media with pumice or perlite for aeration as well as some form of nutrients to improve fertility. I like to add earthworm castings or compost as well at a rate of 15-20% of total media to increase organic matter and biological diversity in the mix. If you want to read more about building soils you can checkout the blog post on 7 Important Things When Building a Living Soil.

I hope this article helped you form a more educated opinion on the subject. Happy growing!

Article Source:

Peat vs Coco Coir

This can be a hotly debated topic among growers as to what's the best media for growing plants. In this article, I'll weigh in with my opinion on the subject as there are Pros and Cons to both.

www.kisorganics.com

Resources:

The Truth About Peat Moss

Does Peat Moss Have A Place In The Ecological Garden?

The Peat Moss Association in Canada

A Comparison of Coconut Coir and Sphagnum Peat as Soil-less Media Components for Plant Growth
Getting to the Coir of the matter
How Coir Is Made
What Your Substrate Is Trying To Tell You
The Importance of Buffering Coco Coir
Nasobronchial Allergy and Pulmonary Function Abnormalities Among Coir Workers of Alappuzha
Philippine Coconut Farmers Warn Over Pesticide Use
Use of Toxic Pesticide on Coconut Trees Assailed
*featured image courtesy of Aravind Sivaraj - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30743840

 

[Waira]

Thanks @KIS Tad! ...a very good summary here -

From what I see in most high quality bagged soils, both are used which seems to be about getting the best of both (performance/features) worlds and lessening the negatives of either alone.
I think a lot of the beefing is more about their use in hydroponic applications?
I know from my years in the Infirmary that coco is a lot more challenging and troublesome because of it's CEC quirks, Ca/Mg in particular, and the sometimes spotty quality issues. Many folks tried using coco like they would peat, and not doing their homework on the rather significant differences between them...And getting jammed up
Mastering coco can make for amazing yields in smaller volume pots sizes vs. peat, but it is a steeper learning curve and many find that fixing problems in coco can be difficult on them and the plant! It's not as forgiving it seems...
There can be more fussing and labor with nutes too generally speaking, granted that's what one signs on for when doing hydro' regardless of medium... But with coco it's definitely a bit more fussy.
I think in peat/peat+soil blends, good pH range is broader and more forgiving than in coco/blends, blame to those CEC quirks in part, and the fact that optimal uptake, availability range is more narrow, akin to fully water hydro's very tight range.. Stray a little, and things can snowball into a mess all too easily!

The hard part in diagnosing and fixing the problem is untangling cause and effect. No small challenge given how intimately tied pH, nute chemistry/form(availability for uptake), and media characteristics are! And true in any medium or grow style...

As for bad batches of stuff, that's universal- Bagged soil, straight coco or peat, nothing is immune... I recall several fine growers who were well versed and loyal to a brand suddenly have WTF-grade issues, often from start to finish. Much head banging and fussing/fixing only to finally reach the conclusion (usually well after the fact) that it was something wonky with their beloved medium. Often proven later only after trying a fresh batch, different lot#!
ProMix had some hiccups a while back, not sure how widespread it was but a few mates I know all had troubles around the same time, all similar issues, and all fixed by ditching that bail for new stuff/different lot...

I had problems with my fav' soil's last season- I couldn't be sure if it was the old Empire Builder that had been sitting around at the store outside for who knows how long, or if the King's Mix (coco based) had shit coco in it...
All I know for sure is that when I shifted to Root Organic Orig. soil for the later started plants, they stopped!
...As usual, all were amended with your fab' Nute Pack -

 

[Mozzy]

All I know for sure is that when I shifted to Root Organic Orig. soil

All I've ever used since I figured out how growing works, is really just Roots Organics Lush and decent tap-water, seed-to-harvest...I don't know what I would do if it was no longer sold locally

high quality bagged soils

Are there other bag soils you would consider equal to or better than Roots Lush (at roughly $10/cubic foot)?:

"ROOTS ORGANICS
LUSH
DERIVED FROM
Earthworm castings, dolomite, limestone, phosphate rock, bat guano, langbeinite, feather meal, sulfate of potash, fishbone meal, soybean meal, fish meal, kieserite, volcanic rock dust, blood meal, crab meal, alfalfa meal, greensand, volcanic ash, kelp meal, nettle leaf and hop flowers

*0.8% Slow Release Nitrogen from feather meal, blood meal, bat guano, soybean meal, alfalfa meal, fish meal, fishbone meal, crab meal, nettle leaf, hop flowers.

CONTAINS NONPLANT FOOD INGREDIENTS
1.5% Humic Acids from Leonardite and Peat Moss
0.1% Beneficial Bacteria and Mycorrhizal Fungi *

*BACTERIA CONTENT
Bacillus subtilis
2,000,000.0 CFU PER GRAM
Bacillus licheniformis
1,000,000.0 CFU PER GRAM
Bacillus megaterium
1,000,000.0 CFU PER GRAM
Bacillus simplex
1,000,000.0 CFU PER GRAM

*MYCORRHIZAL FUNGI CONTENT
Rhizophagus intraradices
0.4 PROPAGULES PER GRAM
Funneliformis mosseae
0.03 PROPAGULES PER GRAM
Septoglomus deserticola
0.03 PROPAGULES PER GRAM

Soil Amending Ingredients: Peat moss, earthworm castings, pumice, perlite, and coco fiber.

Roots Organics Lush growing mix is an amended peat-based media that delivers absolute consistency and control. What makes Lush superior to the competition? Nutrient-rich, this robust mix combines a well-measured primary fertility package with ideal foundational components to maximize yield in mature flowering plants. The precise ratio of peat, coir, perlite, pumice and worm castings has been added to create ideal water holding capacity and drainage. Rich in sustaining nutrients, this media is designed for a water-only or reduced nutrient schedule. In fact, most plants can happily feed on Lush for up to eight weeks without additional support. Roots Organics Lush is ideal for the gardener who wants a heavily amended soil packed with the best natural and organic nutrients on earth."

 

[Waira]

All I've ever used since I figured out how growing works, is really just Roots Organics Lush and decent tap-water, seed-to-harvest...I don't know what I would do if it was no longer sold locally

Well, in truth I hadn't used Roots in years, but I know it's been pretty good consistently for a while now. A couple well known breeders I recall have recommended it, use it themselves in the past at least. That includes Daz/Night Owl - and at the time it was the Original soil.
707 I have used in the past too, that was fine as well...
Lush I haven't tried, looks nice and rich though!
The last 3 years I have gone with KIS's Nute Pack, a dry amendment to mix in and cook for a bit. This has worked nicely for me and as such using a really rich soil base wasn't necessary or wise...

Basically I'm looking to go near-water-only for both photo and auto girls, but I have challenges in that regard. I grow in small volume pots, about 9L for autos, 7-10gal photo's which does limit the nutrient reserves over the life of the plant depending on the usual various factors...
In the case of photo's, the main hitch is trying to keep them to size and not overgrow and deplete early those reserves. You know the dilemma: more volume means more reserves, but then the plant will grow in kind to that volume/demand so that gets you nowhere!

Learning curve lesson #1 - first year they went apeshit in 10's, and tapped out the soil not long after bloom started and had to scramble at the worst time to keep them in condition -
My trick now is to do staged transplants, and later starts (outside always for photo's) to limit veg time and put some squeeze on the roots to slow them down some...
I start in 32oz styro cups, move to what's about 4.5 gal pots until they fill those up enough to get that squeeze (several weeks, not long really!), then at what's usually late veg they go into final pots (fabric) to finish.

I still add various supp's and some light feeding/PK boosting on an individual basis, but the KIS takes a lot of the basic nute fussing out of the equation - ...but this MO has worked better for my grow gig than anything else to date!

Are there other bag soils you would consider equal to or better than Roots Lush (at roughly $10/cubic foot)?:

Several years ago I got turned onto a CA/local soil by my grow shop mate here. Sanctuary Soil in the brand, and Empire Builder and Victory Mix (milder) were the products. Beautiful soils all around! I found it to be a great value, if not "cheap"; 2cf bags were about $16, and so worth it!
I also wanted to try King's Mix, lighter/fluffier due to it being coco based but still a true soil (full complement of amendments, not just a couple-few things)... This is nice stuff too, which I blended with the Empire Builder. KM is fast drying as you may suspect, not good for OD's, but it made for nice blending for the auto's! I found it to be very clean, well sifted, little dusty-fines... Royal Gold has a good rep' that I've know of to date, as a coco product company.
Alas, EB/Sanctuary isn't widely available like Roots...
What happened last year is still not certain... no way to finger the old EB or possible bad batch of KM for sure, only that they were the common factors. The EB was old, clearly sitting around for more than 1 year. Hard to say if it went "bad", not sure how that could happen?

Prior to that, it was Roots, but I've tried Vermicrop, EB Stone 420, and long ago FuxFarms when it was still decent. I got burned by them the 2nd year of growing when their quality took a face first dive- literally- the fucks put out soil in the low 5's pH! Since then, that I've seen, little has changed... Some folks get OK bags, others get shit...
Personally, I wouldn't bury cat crap in it these days! ...you still get what you pay for, like everything else. It's cheaper than most, and it shows in the garbage bits in it (rocks, wood chunks, etc); poorly cooked/processed (pH issues), lots of free vermin bug stories as well =
My grow shop mate stopped selling it for a while, but customers kept paining him about it despite his warnings so he brought it back...
Some folks gotta learn the hard way!

 

[hecno]

@Waira Here is a question for you [ soil based ] When I read about problems about soil [ store bought ] I am wondering why , Now I have never had a problem with my own soil as in pests that I know of , so could environment and aging the soil play apart in pest free soil . As you know I use a lot of inputs that I gather from around my environment and still no pests . .

 

[Waira]

@Waira Here is a question for you [ soil based ] When I read about problems about soil [ store bought ] I am wondering why , Now I have never had a problem with my own soil as in pests that I know of , so could environment and aging the soil play apart in pest free soil . As you know I use a lot of inputs that I gather from around my environment and still no pests . .

It comes down to the soil being "unclaimed territory" for vermin, or worse, already buggy when packaged up...
The bags have small air holes in them, gnats can easily slip in... there are no predators around either of course, so it's bloody party time in the bag!

Your soil is practically fizzing with life; likely gnats are around but can't get much foothold because of that life... Competitors, predators, maybe even pathogens to such vermins... and in your case all local, so balance is built in basically!
...I'm still waiting for my batch to arrive from you...

 

[dankstyle J]

The living coco mix I use consists of coco peat perlite an over the years probably a hundred organic inputs to me it works extremely well

 

[Bruce Campbell]

@Waira @Mañ'O'Green and others:
@Dankerson @JP1 @Mara Cachafa @throxic @Lil Dab @420autoflower - recently had a discussion re: buffering coco.

I didn't want to derail that conversation over there, but had some related questions regarding growing with peat if anyone can provide thoughts or input.

I use Pro-mix HP without additional amendments, mineral salt feed with every irrigation, and germinate directly in the pots. I typically start with a 'nursing solution' that is my veg feed at 50% strength. I try to saturate the pots a few days before planting a bean, but otherwise just drop it directly in the pot. I'm not looking to change much about that process.

1) How would you recommend / what do you do (if anything) to 'condition' peat before a grow?

Peat has the same or higher CEC than coco, but I've never seen or heard anything about needing to (pre)buffer at the start of a grow. You couldn't soak peat the same as coco, but does anyone flush / oversaturate / run-thru with feed beforehand to 'pre-load' the peat at all?

2) How would you expect the calcium / CEC / pH behavior to differ between peat and coco over the course of the grow?

Pro-mix and other peat blends normally come with perlite and limestone mixed in. IIR, I saw somewhere once on the Pro-mix website that recommend wetting a week before planting to allow the limestone (CaCO3) to begin dissolving / mineralizing for pH reasons. So, would peat blends be adding / making available more Ca during the grow vs. coco continuing to buffer out / make unavailable Ca from the feed as the grow progresses?

 

[Lil Dab]

@Waira @Mañ'O'Green and others:
@Dankerson @JP1 @Mara Cachafa @throxic @Lil Dab @420autoflower - recently had a discussion re: buffering coco.

I didn't want to derail that conversation over there, but had some related questions regarding growing with peat if anyone can provide thoughts or input.

I use Pro-mix HP without additional amendments, mineral salt feed with every irrigation, and germinate directly in the pots. I typically start with a 'nursing solution' that is my veg feed at 50% strength. I try to saturate the pots a few days before planting a bean, but otherwise just drop it directly in the pot. I'm not looking to change much about that process.

1) How would you recommend / what do you do (if anything) to 'condition' peat before a grow?

Peat has the same or higher CEC than coco, but I've never seen or heard anything about needing to (pre)buffer at the start of a grow. You couldn't soak peat the same as coco, but does anyone flush / oversaturate / run-thru with feed beforehand to 'pre-load' the peat at all?

2) How would you expect the calcium / CEC / pH behavior to differ between peat and coco over the course of the grow?

Pro-mix and other peat blends normally come with perlite and limestone mixed in. IIR, I saw somewhere once on the Pro-mix website that recommend wetting a week before planting to allow the limestone (CaCO3) to begin dissolving / mineralizing for pH reasons. So, would peat blends be adding / making available more Ca during the grow vs. coco continuing to buffer out / make unavailable Ca from the feed as the grow progresses?

@Frankthetank is the pro mix guy. I never used it only use plain coco and perlite

I think peat holds nutrients more than coco. Coco mostly holds on to ca and mg not much else

 

[Frankthetank]

I just scoop it from the bag into the pot, poke a hole with my finger, dump 1/2 gallon of plain water (I use spring water from the store) down the hole, plant the germed seed and cover, and moisten the entire top of the soil…. I feed plain water until day 7, then start at 25% strength, and work up from there. Easy. I smoke pot. I like easy.