I don't remember using DE - what I get of it is a fine powder, But I bought a bunch of garden additives last year, it wasn't dusty, didn't smell funny, wasn't bone meal - that has an aroma, so I just dumped it in

I finally fertilized my semps about 10 days ago, with Quick Start in water. (half strength)

JungleShadows said: Yes that's why I use JUST Quick Start. It has a relatively low N content and I even use it at half strength when I fertilize.

The irises that are my other big crop do the best with that same range although I can bump the N up on the beardless irises with no problems.

Kevin

I bet those semps are happy. That should bring on a nice flush of growth.

Pics when I get a minute

I have determined what the mystery grit was that I found on my porch and put in my 2022 sempervivum mix. It is basically a ceramic product, intended for use in aquarium plantings, so it will function like grit, and it has trace elements added. It felt like it wouldn't be a problem. Not something that would retain water

That is interesting Alice. What does it look like?

hmm, probably low fired for added porosity, cool amendment Alice. Based on the description I'd bet it'll act like something between turface and pumice, holding more moisture than gravel yet allowing for some aeration and added drainage, just a guess! I use turface sometimes, it breaks up the soil but seems to hold moisture during rainy seasons and desiccate during the dryer ones, so I use it sparingly when I do. Pumice obviously needs no introduction, lots of air and some moisture retention, there's a reason everyone uses it!
-Sol

It's not cheap stuff, I think I will stick with pumice, or at least compare price. This is what it looks like.

I think the rest is going in my aquarium, under a black sand that accidentally became a succulent and semp amendment before I realized it could be a little radioactive. The black sand is made from coal slag, and is widely used in aquariums but I won't put it in my veggie garden.

Would that be good for fish? Radioactive black sand?

How radioactive
Anyone have a meter???

It must be okay for fish if it's "widely used in aquariums". I wonder if it's one of those things that may just be radioactive to sempervivum? Possibly too much moisture retention, like vermiculite?

Question: does LECA retain too much moisture for sempervivum?

I have some I used for orchids, and I wonder if it might be useful to add to the container mix as well, if it were broken pieces?

Wow, that is new to me. Anyone have experience with this?

The only info I can find is in a Bonsai forum. They concluded that it was similar to lava rock in most respects and that pumice retained more water.

But trees are not succulents.

However, although I don't have an easy source for pumice, here, since the closest volcano is Yellowstone, I do have a big bag of LECA pellets.

I don't know how radioactive coal slag is but I have decided to just drop an undergravel filter with gravel in the aquarium and give the coal slag sand to someone that uses it in their tanks. It's probably safe enough, I got at Tractor Supply, it just sounds bad.
It's only in one of my pots, it's sand and we'll see what the plants do, but I won't be buying more. and it's not going in my vegetable garden.

I use expanded shale in aquaponics. If have not tried it in succulents. is that what that expanded clay is? It is supposed to help with water retention.

I have some Leca too, again for aquaponics, though I've not used it this year. I cheated, tossed 2 4 inch pots with tomato plants in a pond filter and wished them luck. At least one is alive

Expanded shale is different from LECA, although it's probably a similar idea.

LECA is expanded clay pellets. I read that they are superheated in a rotating kiln, which is why they're round.

So kind of like porcelain, but not quite?

I also looked for Permatil, which was mentioned in this video.

https://m.youtube.com/watch?v=...

It is expanded slate, but I can't find it for sale near me. I'd have to drive at least an hour.

FPF, you should do an experiment using the LECA as the main ingredient, with a bit of potting mix (forest type). I think OldmanDan uses pine bark for his semps.

valleylynn said: FPF, you should do an experiment using the LECA as the main ingredient, with a bit of potting mix (forest type). I think OldmanDan uses pine bark for his semps.

What would you suggest: crush it first, or no? Or try both ways?

PS: actually, never mind. I think I have two pots exactly alike that I will use and just do both ways.

GeologicalForms said:
Biochar is pretty expensive but the semps do like it, you can collect your own charcoal from the fire pit (which works fine) but to make a similar substance to the biochar sold at nurseries you'd have to remove the dust and boil then dry it, I've heard that "activates" the charcoal so it's nutrients can be more easily absorbed, but I just throw mine in there raw at 1/9th of my mix.

Charcoal needs more than that to activate it for it to be biochar. It first needs to be wet down, because it is resistant to water. After that, it needs to be "activated" by placing other stuff in it - compost is great, but other popular things include molasses, urine, flour etc. This allows the charcoal to become a "condo" to nutrients that microorganisms can thrive on. Adding straight charcoal to your soil will eventually become biochar, but to do so it will leach nutrients from the soil which will take them from the plant.
https://www.ars.usda.gov/midwe...
I make most of my biochar from the charcoal in my wood fireplace. Works great.