imafan26
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Alternatives to Peat moss in container mix

It has been harder to find good peat moss and I heard that because of the drought and politics, not only has supply been impacted but it costs a lot more. I even noticed that MG potting soil is not the same, they are replacing more of the peat moss with composted forest products. At the garden shop, I am seeing more coir being used but the plants don't look all that healthy.

I have used coir in aquaponics and it is o.k. for root crops like radishes and carrots. It works o.k. for plants that like to dry out between watering or tolerate saline conditions. It does not work as well for plants that are tall and have a tendency to fall over or plants that don't like drying out.

The plants I have seen growing in them were mostly organically grown. They looked yellow and sickly. I don't know it is is the coir or the fertilizer that is at fault. Has anyone used coir and what were your results?

For some things like the citrus trees, succulents, and orchids I can use cinder instead.

I have poor results adding more than a couple of handfuls of vermicast to the potting mix and poor results replacing compost for part of the peat moss.

What is in your container mix for potted vegetables and how often do you water?

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digitS'
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Imafan, nothing to suggest as alternatives.

Black Gold standard has been my choice for decades. An earlier near-disaster with a hardware store brand for starting seed made me very apprehensive about experimenting. I have ventured enough to try a sterile seed starting mix on "non-essentials" but have been a little frustrated with having to deal with fertilizers within a couple of weeks.

That said, the potting mix has changed in the last few years by my guess. The nearest garden center now carries a BG starting mix and that is when I first noticed the change in the all-purpose organic. It was always a little coarse for smaller seeds. It is now coarser with a good deal of bark. It isn't forest litter by the evidence of a few bits of plastic that show up in each bag. It includes municipal compost is my guess.

Sun-Gro makes not only Black Gold in a couple of varieties but many as well as a Sunshine line for commercial growers. Trying their more expensive small bags of starter mix is a possibility. I'm likely to be in the market for new ideas the next few years.

Homemade compost is fairly good stuff. Not only do we save kitchen peelings of which there is many but selling at a farmers' market for several years meant that we had not only lots of use for commercial potting mix but several 5 gallon buckets of "spent" mix from up-potting. I am also inclined to step over and take a shovel full of the best of my garden soil to top off the compost.

This material will be mixed with peat moss and perlite in equal portions for potted perennials. Other than some herbs, only a few tomato plants of the vegetables stay at home rather than go out to the garden. They are in straight compost and, pretty much, thrive. In the high heat, I'm watering them every day. Usually, it is every other day.

Steve

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applestar
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It’s difficult to suggest anything since the entire environment you have is so different from what I know.

Keeping in mind that everything is imported by sea or by air, is there anything that is locally sourceable? Or are anything remotely useful snatched up by market farmers, etc.?

Did you see my post on alternative bokashi made not with rice hull but buckwheat hulls? It remain to be seen how well that blend performs, but I’m encouraged by the progress so far, and really think similarly processed materials have high potential, and something that is sand sized would be an excellent amendment for potting mix — so of course the obvious candidate is used coffee grounds.

I feel like there ought to be other tropical plant based material that could work — coir was a good idea to use the coconut husks … what else is there that absorbs and holds moosture but won’t immediately break down?

What about palm fronds dried and ground up? fern roots? vines and plant materials that you can make textile or rope out of?

If there isn’t an industry already creating the ground up or shredded or something as waste you would have to find a way to make massive amounts yourself — food processor, chipper shredder, leaf chipper, run over with lawn mower …..

I know you were asking about ready-to-use materials, but I can’t think of anything except coir that is industry standard.

Are you able to easily obtain rice hulls? I know that is being marketed as perlite alternative, but once fermented as bokashi, it does absorb and hold on to moisture.

Maybe

imafan26
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I like black gold but not many stores carry it. I found black gold potting mix in small bags and that would not be cost effective. I have not found the black gold compost which I do like at all.

I only have a worm bin and make small amounts of vermicast. I don't have a compost pile. When I did have one, I had more greens than browns. I did bag composting which does not make much either. Many of the leaves I have cannot be used for composting because they have problems like plumeria rust. Tropical trees are not like trees in temperate climates, they are evergreen and don't shed many leaves. Plumeria are not native to Hawaii. Frangipani plumeria shed their leaves in the fall. I only get larger volumes of leaves when I trim. I only have to do that a couple of times a year. My friend gave me a bag of lychee leaves. I am going to use that to repot the anthuriums. They like to be potted in leaf mold. I can only use the bilimbi for composting because it generally does not have many pests and it is not sprayed. Palms take too long to break down and roses are sprayed with systemics to control black spot. They cannot be grown organically here.

Plumeria and ti have rust. Weeds will survive cold composting. Nut sedge will survive hot composting. The garden waste that is good is fed to the worms. I do some trench composting in the garden. The rest goes into the city recycling bin. The green waste compost made locally is not of good quality. It has a pH of 8.13 the last time I checked, and my mom complained she got weeds (nut sedge) from using it.

I do have nematodes in the garden and that is why some plants like tomatoes and edible ginger are planted in sterile mix in pots. Not all of the tomatoes are nematode resistant. That is how I found out I had nematodes in the garden. The nematodes were on the kale and tomato in one part of the garden. They were stunted but limped along. I only discovered the real reason they were like that when I pulled up the roots.

I had been reusing soil because it was hard to get perlite and peat moss for a time.
Now, I have problems with root mealybugs. I can't easily sterilize the soil. I can treat only small amounts of the soil. Hot water will kill the mealy bugs. The other alternative is repeat treatments of malathion or diatomaceous earth. I have used both alternatives. They do work but take more time and 2-3 treatments. The pots have to be bleached.

I could add good quality compost to my planting mix if I could figure out how much to add. It would reduce the amount of peat moss I would need. I have tried it before, but except for a couple of handfuls of vermicast, compost holds too much water and nothing grows with any amount of composted manure in pots.

I don't know if combining coir with peat moss would be a benefit. Coir has a lot of salt and potassium and it needs to be washed to get that out. It is why salt tolerant plants do better in it. The high potassium can cause problems making other nutrients like calcium and magnesium, less available. Coir has a pH close to neutral which makes it less desirable for acid loving plants, but o.k. for plants that tolerate a higher pH.

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digitS'
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Imafan, if you would like to look at some recipes for certified organic potting soil. The National Center for Appropriate Technology has a brochure.

https://attra.ncat.org/product/potting- ... roduction/

It is a 24 page pdf file. The final page has the recipe that I use for perennials under: "Vegetable Transplant Recipe, Adapted from On-Farm Composting Handbook, by Robert Rynk, (ed.), 1992." However, there are recipes with components other than peat moss.

Steve

imafan26
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Thanks Steve
The article was perfect. I just harvested the worm bin yesterday. I spent two hours sifting out the worms. I have to wait another week to sift it through again. I have always been able to add a couple of handfuls of vermicast to my potting mix, I just don't have a constant supply since I harvest the bin once every three months.

The article says my mix should still be about 60-70% peat moss and maybe 20% good quality compost. I'll have to find that. The article suggested 2 parts peat moss one part compost and 1 part perlite, but I know that won't work and it will be too wet for the way that I water and for the rainy season. I'll have to play around with the mix. Maybe (3 parts peat moss, 1 part compost ) mixed together and use 1 part peat/compost mix and combine that with 1 part perlite and tweak it from there + osmocote.

Most of the organic fertilizer like greensand and colloidal rock phosphate are not readily available unless I go to an ag supplier. I can get epsoma products at Lowe's or Home depot, but I am not into doing organic in pots anyway. I don't object to using organic components but I have no problem using slow N synthetic fertilizers that are easier for me to get and carry. I test my soil. I have already figured out how much fertilizer I need for each of the pots for the plants I grow.

I have tried organic fertilizer in the soil before and I like bigger productive plants and longer ears of corn. I plant intensively and to get enough nutrients, I would have to plant fewer plants and supplement nitrogen more. As it is, I only supplement nitrogen anyway since my soil is actually extremely high in phosphorus and high in just about everything else. I only need a quarter cup of sulfate of ammonia for 128 sf of the main garden. I only have to do that once or twice as side dressing for each crop. Potted plants are supplemented with MG water soluble once a month or less. I have to fertilize some orchids, anthurium, and succulents this way since they are not grown in any media. Anything left over is given to the potted plants. The perennial and long maturity crops do get additional 4-6-4 slow N fertilizer with micros every 3 months as a side dressing. I found I don't need high numbers. So, I try to stay with numbers under 10 and I actually found some general purpose 10-10-10 (once. That should last me a while since it was a 20 lb bag.)

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applestar
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I just came across this recycled paper pulp product in one of the paper catalogs. It’s being offered at $15.49 for a 2 cu.ft. bale with $10 off catalog sale. That seems a lot compared to peat moss?
(as comparison, PBH rice hulls bale of 7 cu.ft. is $13.13 in the same catalog. This catalog offers volume discounts btw)

This is first time I’ve seen it, so I think it’s close to retail price and price may fluctuate.

I found the manufacturer’s link fyi—
Prime Organic Soil Conditioner | PittMoss
https://pittmoss.com/product/prime/

HoneyBerry
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I wonder if a natutal cat litter might work.
Not the kind with deoderizers, etc.
I don’t use it but there must be some 100% natural cat litter products that would be safe to use.

imafan26
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Someone in the bonsai club told me that cat litter could be used in place of turface. I does have to be washed of the dust so it won't clog. I haven't tried it yet because I don't have mini bonsai. I have bigger bonsai and I use black cinder for that. For bonsai, the media is mostly fine graded gravel or akadama.

The cat litter might work to replace some of the perlite, but not the peat moss. It might be useful for succulents since they like a more neutral pH. I have some 2 inch succulents I could try it on. Even subbing out the perlite is not a bad idea. Clay cat litter is a lot cheaper and easier to find than perlite.



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