Prime Agra - Reuse or not?

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Jun 6, 2006
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Sacramento, CA. Outside w/ Southeast Exposure
For those of you who grow using the clay aggregate product marketed as Prime Agra - do you or do you not re-use it when you repot? The condition I'm most interested in is, when perhaps, you send a plant off bare root for another to grow, do you then clean and sterilize the media that the plant was potted in and use it again when potting up a different plant?

Thanks, H
I reuse my Prime Agra. I put it in a pot of water and boil it but it would be possible to sterilize it in an oven as well. If I am repotting the same plant into a larger container, I don't sterilize it first, I just add more to the larger pot.
What's S/H? I dont reuse media because if a plant died in it or needs replanting generally the salts from fertilizing, pathogens [virus, fungi, pests. etc.] may remain in the media. Why not use fresh stuff? E.
Prime Agra is an expanded clay pellet. It doesn't break down for it is inorganic and there shouldn't be a problem if it is sterilized prior to reuse. I never reuse organic mediums for your reasons stated plus others. S/H = Semi Hydroponic.
I use a various mixes depending on what the plant is doing. I use coconut chips [roots love this stuff], diatomite [retains moisture], bark[just because], sphagnum moss [if lots of moisture is needed], agricultural charcoal [filters impurities], and aliflor (baked clay pellets) [if drainage is required]. I have all my phrags in growing trays w/ R.O. water pumped among the bottom of the posts. How does sterilizing remove salts from fertilizing unless you soak them out? E.
that is why I boil, the salts disolve in the water. With S/H the pots are flushed out on a regular basis and there isn't a large build up of salts to begin with. You must need to change your medium on a yearly basis with your culture. Did you see the link I added to my last post?
Yep, thanx for the info. I will change my medias more often than that. Do you use R.O. or distilled water to boil the pellets and doesnt boiling concentrate the salts? E.
I put mine in the oven at 500 degrees for 30 minutes. That'll kill pretty much anything.
NYEric said:
As soon as I can I will send photos of the gowing trays and teh root growths w/ this method. E.
are they ebb flow trays? I find amazing root growth with this medium too. The best part is that it never breaks down so it never needs to be changed. Potting up is a breeze for the roots bind the medium together. I don't have a problem with root burn from salt build up, the pots are flushed at each watering.
Nope, they are the cheap tupperware type trays you get from National Wholesale Liquidators on Broadway near Houston St. I use R.O. water and a Fluval 1 in each tray pumps the water continuously. I have 6 trays full of Phrags and fertilize 2 trays at a time for a few days in separate fertilizing trays so I'm constantly moving and working w/ the plants. It's a little busy but I get to constantly check the plants. E.
Ron-NY said:
You had a concern with reuse of medium and disease spread but you don't with multiple plants that are sharing the same water :confused:

I wondered about that too.

How long do you boil the PA for, Ron? That's usually how I pre-treat new PA. Also, FWIW, the plants who's mix I would be reusing are not sick or dead plants, just going to new homes and I'm short on prime agra! :)
Wrap in foil, bake in oven at 500 for 30 mins. Way easier and kills some viruses that can survive boiling.
I don't usually bother to boil mine, but I do soak it in Physan for a while. If you used it long enough that you think salts might be a problem, Id either boil it or rinse it for a good while.

- Matt