Bit of a rant; garbage potting soil

I haven’t bought potting soil in ages but being at home depot, standing in front of a pile of bags, and having a bunch of saplings to pot, I figure I would splurge and pick a bag instead of making a batch. Sweet baby Jesus this stuff is garbage. The last time I bought “premium” potting soil it was this great humus-like dark rich soil looking good enough to eat. Ok, probably not that good. But still; this “premium” vigoro potting soil seems to be little more than crunched pine bark with a smidge of slow release fertilizer granules.

They should sell it as self mulching; after watering the chunky bits of pine bark float up covering the surface.

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Vigoro is Home Depot’s brand name. They hire regional manufacturers to make it.

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Peat moss doubled in price this season. Home Depot in our area didn’t even carry it. The best commercial formulations of potting mix around here are usually based on Cornel’s old peat-lite formula and are mostly peat moss, not that other formulations can’t work as well- I wouldn’t know. I always use at least a third peat in my home made mixes to assure drainage, along with an equal volume of perlite for both drainage and lightness. The final third is compost, which holds more water than peat and helps the peat absorb water without adding an absorbent- it also brings up the pH just enough and add plenty of nutrients. If weight isn’t an issue I may sub the perlite with sand.

I brought a neighbor a couple of tomato plants and he said he’d just bought crap potting soil on sale from home depot. I opened a bag, and it was a pretty good version of peat-lite that slow release fertilizer was added to. I told him it would work just fine.

A tale of two home depots, I guess. I don’t remember the label on the bag so I can’t say for sure if this fell within Richard’s explanation.

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I don’t recall ever buying potting soil.

I have bought composted peat (garden magic) which is a very nice product…

I do buy some black kow (50 lb bags) a composted cow manure product… very nice… has a stated NPK of .05 .05 .05.

I make 400 - 500 lbs of homemade compost each year.

When I do pot something… I normally make a custom mix of real top soil from my field or garden… and either homemade compost and/or black kow… and composted peat. I add to the mix blood meal bone meal Epsom salt green sand, gypsum.

I just put all that in my wheelbarrow and mix it up good then pot with it. If there is any left over… dump it back in my garden or compost pile.

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Spend the money on ProMix HP or BX. Or Happy Frog. I bought a couple of small bales of ProMix All Purpose from Menards because it was super cheap…its garbage…

I have some ProMix HP and Happy Frog in various wicking tubs and after 5 years they still have enough nutrients to give life to my cuttings and propagations.

My local Home Depot usually has $1 bags of leftovers in the Fall… faded sun damaged bags that barely are still together. I usually buy 50 or so bags and load up my flower beds and planters… but yeah they are all garbage…

I think the formula for box store potting soil is ground up tree stumps, some gravel, and contaminated top soil with a touch of mold and insect larvae and worm eggs.

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Last time I bought something from Home Depot, I managed to kill one plum tree. No more. I’ve been mixing my own worm compost with my garden clay and a bit of dirt from Costco. But even then the bag of dirt from Costco is not cheap, $9-10 for junk. From now on, I will recycle my own clay and my own compost, much cheaper and healthier.

I just read this article about “forever” chemicals in commercially produced compost: When organic is toxic: How a composting facility likely spread massive amounts of ‘forever chemicals’ across one town in Massachusetts - The Boston Globe
Made me wonder if the various soils, manure, mulch and compost sold by big box stores might contain these dangerous chemicals.
Also recall a long time ago, Rhode Island was promoting sewage sludge as a fertilizer. I did not feel it was safe to use because of chemicals and heavy metals. You might find these articles of interest:
Sludge in the Garden: Toxic PFAS in home fertilizers made from sewage sludge
Sludge News | Branded products containing sewage sludge

Reading the article it seems strange that they were including apparent sewage waste in their compost, which is often high in toxins. Also, the article did not clearly explain how the compost company is factually linked to the water contamination. Given how hard the company has been hit, I assume the pollutants in the ground water were also found in their compost, but it may be a coincidence, based on what is in the article.

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you got the same problem i do. finding enough compost to make your own soil. ive killed many plants/ trees with that garbage stuff and with rec. weed legal the good stuff goes for $50 a bag here. i have chic bedding but it takes 3 years of composting before i can use it. instead i use it as mulch letting it compost in place. used to drive down to Machias on the coast to buy Coast of Maine compost by the truck load. then they figured out they could make a fortune by selling it by the bag. too bad as its great stuff!

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Here is the Boston Globe article:
PFAS.docx (185.9 KB)

It opened the 2nd time I tried your original link- so I rewrote my comment.

@alan I suspect that they included sewage to increase their bottom line. I agree that it may be a coincidence that there were the same pollutants in compost and ground water. I suspect that homeowner law suits will bankrupt the composting company and its owners.

The sad thing is that my own potting mix is petty darn good and it is mostly sand (strong winds here) and well cured horse manure. Maybe a pinch of vermiculite and if for a cuttings bed a good amount of perlite. I use peat moss for starting some cuttings and that ends up getting recycled on a batch of mix.

Each year i get several pick-up truck loads of horse manure which i just pile up for use the next year. I also put a lot of home produced urea on it.

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Have you tried Timberline Top Soil? I get it from Lowe’s and found it to be fairly decent. That said, it seems to hold water (at least in my experience).

I had two sets of kinds of soil in pots this year. Soil from Costco I bought at 8 dollars and a mix I did with Osmocote fertilizer, peat moss and perlite for drainage. The plants in the Costco soil pots have hardly grown while the ones in my mix can’t put out enough growth. I can’t stress making your own potting mix enough because a thing of peat moss is 11 dollars and perlite is 18 dollars from Home Depot. Fertilizer is more expensive at 28 dollars last I checked but you need to buy fertilizer anyway

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ive been buying the cheaper promix . mixed with perlite, and osmicote plus and a handful of dolomite lime. so far its grown well. prefer compost but hard to come by here.

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Sounds like promix would be super easy to replicate as that is pretty much the mix I thought of making myself minus the lime. My water already has lime deposits in it and it actually has so much lime in it that deposits build up around faucets. I am sure that lime is naturally occurring in where I live meaning it is the same mix. How I thought of my mix was simply one year I had only peat moss and that retained too much water. In fact it retained so much water my mulberry did not need to be watered from between December to July or August in a pot. I had a moisture gage and it was reading at a 10 for most of that time with pure peat. That wet of soil is going to cause issues with peat. I use a half a gallon of perlite in my mix but I use 100 gallon planters so I have 9-12 feet of peat moss as well in those pots. As a result I got perlite to aid in the drainage as that is what the label says. I knew the plants had to eat hence the osmocote. Anyone who understands how amendments works in gardening could do it and if you don’t mind getting dirty mixing you can get it much cheaper than premixed soil.

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Coarse sand is a very underrated potting soil additive:

  • Here it is windy AF, sands makes them heavy and more stable.
  • It provides ideal drainage that enhances the water retention of the other components.
  • It does not compress; if your usual mix shrinks making it a pain to water (water runs down the sides before it can soak the soil) sand will help with that.
  • It provides better grounding to roots; a number of potting mixes are too soft for roots to properly anchor.
  • In ground, earth worms need sand in their digestive tracks. Pure organic mixes are not healthy for them.

Most of my in ground plants are on 50/50 native sand and horse compost, they seem extremely happy. Year after year I add green tree mulch on top. It furthers break into the soil creating a humus similar to forest soil. Cuttings may get less compost and a healthy dose of perlite to make it easy to uproot them. My potting mix uses vermiculite instead, 1/1/1 sand / vermiculite / compost.

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is it sand or gravel? i have access to fine river gravel. think 1/8th in. texture. i think of sand as the yellow sand we have on the coastal beaches in s. Maine. i always add extra perlite to my mixes but gravel is free from the gravel bars along the rivers.

Pretty gravely. As you know my soil is rock/sand or a gradient from grapefruit size river rocks to fine sand. I sift it with a 1/4" screen so it goes from fine to slightly chunky.

What you have is great stuff for use in soil. Lots of plants prefer to sink their roots on something with more texture than purely organic potting soil.

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