I have about 10 varieties buried horizontally in 16 oz cups mostly, with a few in Glad storage containers. I just planted them straight in 70/30 perlite, seed starter mix, just below the surface. They are sitting in a closed container. Never starting them in any matter. Just straight in. Some were completely buried. Some were slightly exposed. The one that didn't root so far might have been buried too deep.
The cuttings are about 3 inches long with at least 3 nodes. Some in containers are a bit longer.
I mist them every few days so the surface doesn't dry out too much, until I see roots. After I just wait til the moisture on inside evaporates, then I water when necessary.
I have thin and thick roots appearing.
I have a Siclian Red ( Thanks Northeastnewbie) in a quart Glad container that is EXPLODING with roots.
This has been the Most successful way to root for me.
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Dominick
Zone 6a-MA