(in response to...
Rot? by DisEmboDied )
just leave them alone whatever they do, when moved to new environments, they stunt and like okay its hard to explain. I don't know about colder climates, but where I am at, its pretty hot and what ends up happening when I root cuttings is... the entire body of the original cutting will start to kind of soften up or even suck itself up while at the same time form roots where the sun won't hit(under the soil), and use that to provide nutrition for the new growth that happens at the top. you will notice the the new growth on the tip when it starts new growths in a new environment will be harder than the cutting itself( only with cuttings , not pre-rooted cacti) so you feel that hardness of the tip but softness of the original cutting maybe its just my environment, but yeah i'm always happy as long as the new growth is hard to the touch, and there is roots to provide for the growth like you know there is life activity. then you just leave it alone water depending on your environment do not let the roots not have water for more than at least 3-4.. 5 days... that is the most I would let a cactus of mine not have water when knowing the roots are dry.
*so the new growth on the tip, always seem to be the one that is familiar with it's new environment * - (key)
once you got enough growth that is familiar with it's new environment and it even knows it self what it is up against in order to survive that will be the new part of your cacti that will thrive in that new environment if you have a cutting from somewhere else growth rate will change, and you will see either slimmer or fatter new growth.
really tricky when sending a plant that is used to (x) temperature... y(humidity) to just (c) & (d) it just has to re -write everything which kinda causes shock but adapts really great cacti when it comes to adapting but you will always notice previous not being able to continue that way because its not where it was when it was growing like... "that".
I hope this makes sense, i'm not an expert i just have a couple feet of cacti under my belt hoping it helps, the thing is the same widths you get the cuttings wont always be the same where they go, and also choosing when and where and what and when they start rooting and the seasons, also... yeah roots never form around winter or anything trust me i tried.... all winter no roots in soil... all the sudden spring.. BAM roots. on every cutting no matter what. its crazy but awesome plant really sweet to learn basic cacti gardening with. any good chunk of it will always bring more, if rooted right, key to rooting (not winter...don't rot it with water... leave it alone) they do their own thing seriously they are the ones figuring out how to survive where they are at.
ill atttach pictures of my currents to show details of what i'm talking about above.
just let me find my camera though !!