Perlite alternatives

[DabberDog]

I ordered straight coco instead of coco/perlite. Got to looking around for perlite for the mix and got to wondering if there is an alternative like vermiculite or the ilk.

[Rootsruler]

Vermiculite would be my choice if you are going pure coco. If you were adding peat to it then I would probably go with perlite but the vermiculite will help with water retention in the media.

[golfnrl]

I've heard of using rice hulls but haven't ever seen them for sale around here. Same with vermiculite. I've used clay pebbles but they were a hassle. So it's perlite for me, I like the larger size, #3 I think.

[DabberDog]

I looked at vermiculite. From what I read, they seem to be complete opposites. Perlite makes for more air space. Vermiculite makes for moisture retention. Same-same for rice hulls.
My considerings:
This is soilless so vermiculite and rice hulls seem a more logical medium.
I've used perlite up to this point and have not heard of using vermiculite as a substitute.
I don't understand how perlite makes for more air space if the medium is kept moist. Does perlite dry out in wet coco?
My water is air stoned before use, so stagnant bags aren't an issue.

[Rootsruler]

Vermiculite has the same size and spacing properties as perlite with the added bonus of better water retention. If I was in a peat/coco mix then perlite all the way. The peat will be responsible for water retention but coco has very little water holding capacity so the vermiculite can help in that respect.

[DabberDog]

Huh? Every other source I see says coco holds 10 time its weight in water and is excellent for water retention. That's pretty much its thing.

[Rootsruler]

Sorry. You're right. I was in the middle of messaging someone else and got confused. My bad.

[ductwizard]

if perlite is basically just taking up space, couldn't you use gravel. i only ask because i'm trying to get my soil grow to drain better and i have gravel laying around

[DabberDog]

Back to my question about how perlite aerates if it is kept in wet coco.

[Rootsruler]

You are correct except for one thing. Gravel will sink to the bottom of the pot into the perched water table and raise it making overwatering more likely. Perlite will stay mixed in the soil for the most part unless it is near the surface. Perlite floats so that is why you see pictures on here with tons of perlite on top.

[golfnrl]

My understanding is the perlite allows aeration by the texture and makeup of the mineral itself. There's gaps and spaces along the surface of the perlite that give room for roots to breathe.

[apacin0]

I used hydroton (clay pebbles) with great success. It aerates and improves drainage (not that coco doesn't have great drainage by itself) just like perlite, but it's heavier. It stays in place in the coco, doesn't sink or float. It's not as cheap as perlite, but it doesn't degrade easily and can be reused.

I'm currently using perlite, but I'd use hydroton again. I'm thinking about ordering it for at least one or two DWC buckets.

[DabberDog]

I dig those little balls but what I see is washing them for reuse.

[Allenpro]

Yep those will work too

[Bluey]

100% coco works fine

[Allenpro]

Yes you can grow in pure coco coir but from the times I have tried it (2) for the price of perlite/Hydrotron I would use one or the other

[apacin0]

I've done 100% coco coir before and it works. I used a small pot, I can see it getting more expensive with big pots. Fluffing the coco up with some other medium I think does help with total cost for larger volumes. I think if you're going to reuse your mix, the clay pebbles are the better route.
..Also get some dang new coco lol. The stuff I buy is very fibrous and full, not powdery. Maybe mix that powdery stuff with new coco, if you really want to save it.

[Rootsruler]

I wouldn't the powdery silt will collect on the bottom and choke out your roots.