what is rockwool, and where can i get it in canada. thx aki

Just let the roots grow and plant the cube in the new container. They also have plugs made of Peat that feel like foam rubber brand name Root Riot.
As far as I know there is no disadvantage with either they both are clean hold moisture well no bugs no bacteria. I myself use the peat plugs since they kinda look like dirt and are a little more obvious as they dry out.
With the rockwool there are even larger cubes ( 4in x 4in )with plastic wrapped sides you just put your plug in, put in a tray and take your plant to size for spring planting. If you go that rout use a complete fertilizer since there is nothing to feed the plants in the rockwool.

I have used Rockwool and had mixed results. Between the peat plugs and rockwool, I believe peat came out better.

It was harder to see the rockwool was kept wet and the seeds did not dry out. I had a lower germination rate with RW. With peat, it was much easier to see and better results.

With germinated plants, I put the whole thing in a pot. If you removed the rockwool to early, it ripped off alot of roots. It is also not degradable so you sometimes see it in leftover soil.

You can buy on Amazon (Canada or US) or EBAY. Nursery's also carry. Also found in Hydroponic stores. They use it for clippings and cloning mostly.

It is expensive too, keep that in mind when compared to peat pods.

This post was edited by RonnyB123 on Wed, Oct 1, 14 at 16:29

Grow2can, I do not know where it could be available in Canada but it will be very easy to find. You can buy it from ebay or amazon, RonnyB already mentioned it. To me it looks like the same material of building insulator. For further information use the link, Just I found from the internet untreated Rockwool pH (probably building insulation Rockwool) level is high so we should be careful. What I use is for hydroponic gardening (treated RW I believe).

Randy and RonnyB thank you for the information, both of you provided me the information I was looking for.

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Here is a link that might be useful: Rockwool

How long should I keep the seedling in the Rockwool?
forever, trying to get it out will probably break the roots

Should I remove the Rockwool when I do re-pot?
^no, you can poke some holes or make some cuts in it so the roots have easier access to get out.

Is there any disadvantage of using Rockwool?
it is nutrient less so people usually use them to start off hydroponics. If you keep them in there past 2 sets of true leaves without transplanting you will have to water them with a hydroponic (water soluable fertilizer) solution to keep them growing.

OKGrowin, thank you for the good answers.

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