This is probably a dup but SO isn't pointing me to a suitable one right now.
I own an overgrown pelargonium. It being huge is not a problem; it being smaller wouldn't be either.
When I was transporting it some time ago a bunch of branches broke off. I placed them in water and reasonable light. In several weeks about 20% of them rooted. The rest never rooted until starting to disintegrate after two and a half months. After being planted 100% of the rooted ones survived.
Now I need to create several new plants from it.
How do I do create new plants with efficiency higher than 20%?
Note: it's rather cold (5-20°C) and dim(cloud cover 97%) around here now but I need to do this quickly.
Quoted timespans are from rusty memory, not factual.