What do I add to finished compost?

[baileysup]

I want to use a peat free compost to make my own potting soil with. Can I just use it straight with some pumice, and possibly sand? Or should I add some coir, since there's no peat in it. This will mainly be for succulents, but I do have a few foliage plants as well. I realize the succulents need better drainage than foliage plants. Wouldn't the coir be a good idea for aeration of the soil, since there's no peat in it? Thanks `

[rainbowgardener]

Why is it you want peat free? If it is for better drainage, then adding coir negates the effect. The coconut coir is a substitute for peat that accomplishes the same things, which are loosening the soil up a bit, making it lighter and fluffier AND holding water. If you are avoiding peat because of its acidity, then coir is a good substitute being pretty close to neutral (pH 6 -6.8 ). Coir is also easier to re-wet once dry than peat, which is good in a cactus mix that you want to dry out between waterings.

To make a free draining cactus mix, you can use some compost, some coir, maybe some bark fines, but mixed with a whole bunch of something inorganic, pumice, perlite, chicken grit, sand, etc. I can't give you any exact recipes, because I don't grow cacti and succulents.

[baileysup]

If you are avoiding peat because of its acidity, then coir is a good substitute being pretty close to neutral (pH 6 -6.8 ). Coir is also easier to re-wet once dry than peat, which is good in a cactus mix that you want to dry out between waterings.

I'll be getting an agave shortly, and I read from an agave grower that they did not like the acidity of the peat. I am just trying to give it the best home possible, though I wonder how much better they will actually grow without peat. I guess it's something to look into for the future, because I'd have to get the coir online. Nobody sells it locally where I am. The plant will be here in a couple days, so I think it will be planted in a peat based mix until I can get some coir. Thanks for the great reply rainbowgardener. It was very informative.

[baileysup]

Just being curious here, but what if I didn't add any organics to the finished compost? I would add a ton of in-organics though, like pumice and sharp sand. Would it be to muddy and compacted? I would think there wouldn't be as much air in the mix without peat or coir.

[baileysup]

Ok, I couldn't find ANY composted bark ANYWHERE, so I bought a bag of mushroom compost from a local. It contains no peat, and it looks like good stuff (nice and black). I hope it's not too good, as in too nutrient rich, for my agave. I don't plan on using more than 1/3 of it in my mix, and it will also be diluted with the coir that I just ordered off ebay. I guess my main question now is, do I mix it with pumice and sand, or just pumice?

[baileysup]

Or I could leave out the compost all together, and just use the coconut coir as the organic. Just coconut coir, and pumice. What are the thoughts on that one?

[baileysup]

Ok, just to prove how really confused I am, is a bark based soil-less potting soil made with crushed bark or composted bark. The guy that grows the agaves says to use bark based soil-less potting mix, but to stay away from compost, as it breaks down too quickly (no I can't get a hold of him). I am confused, and the agave will be here in a couple days. Please help.

[rainbowgardener]

the bark based potting mix will be just chopped up bark pieces, not composted. Your agave could be in a mix of just coir and perlite (or whatever else inorganic you are going to use), 50-50. Or it could be in a bark-coir-inorganic mix. Or it could have a little of the mushroom compost added to the mix. I use mushroom compost in my potting mix for seed starting and seedling growing and I like it, but it is pretty rich and moist. Mushrooms sprout from it! So you would want no more than 1/3 mushrooom compost, maybe less.

It's not rocket science! There are lots of different combinations that would be OK. You just want to avoid too moist and too acid.

[baileysup]

Ok, I did another search, and an old Helpful Gardener post popped up about this very bark topic. It appears that if I can locate a bag of regular bark, I can just crush it up myself for the mix (somehow). Then I will screen it for size. Thanks for the help again rainbowgardener. I really didn't know if I needed crushed bark or composted bark. I do want to try and get the bark for my soil mix, because I think it would make for a better final mix, than just using straight coconut coir. I just want to make the best soil I can for my plants. Now I will search for a bag of bark. I wonder if I'll be able to find some.

[baileysup]

Found it! The stuff is everywhere!! Walmart and probably every large box store has it! That means it could probably be found locally as well. It's the composted bark I couldn't find. I'm glad I don't need composted bark. Just have to come up with a good way to crush it, and that could be fun. I really appreciate all of the help on this one, and my agave says thanks too.

Actually the search was for all walmarts, and mine does not carry pine or any bark. The lowes by me has pine bark mulch. It comes in light brown/golden nuggets, and dark brown nuggets. Not sure if the color makes any difference, other than cosmetic, but I think I'll go with the dark brown nuggets of pine bark mulch. This makes me happy.

[rainbowgardener]

The color doesn't matter if it is natural. A lot of the commercial bark mulches are dyed and I would prefer to avoid that.

[baileysup]

Ok, I got some pine bark nuggets today, and they are natural with no dyes. I will have to crush them up, and I could do it by hand, or buy a cheap blender to see if that works. I don't think it matters much if I screen it or not. The company that makes the pine bark nuggets, also makes a finer version they call "soil conditioner". It's basically finer pine bark particles that have been screened already. Unfortunately I have been unable to locate this product anywhere, but I spoke with a rep from the company, and they said they might be able to help me locate the finer pine bark. I just have to call them back when Jeff is there. Apparently he's a horticultural genius. Just wanted to update, but it looks like I have what I need to make a mix for my agave when it shows up. Just have to mix it now. Thanks again rainbowgardener.