You definitely can as long as you don't trim them back too much. Mostly what happens when you trim roots and replant is that the plant will make new roots.
Perfect! Thank you all very much! I'm trying to plant crypts, switching them from sand over to fluval stratum is exceedingly difficult, I hope trimming them back will it easier for meYou can definitely trim most roots back a huge amount. Usually trimming roots encourages new growth, exactly as trimming the top part of the plant would. Obviously the plant needs some root to survive (more or less depending on species) but the long trailing parts are generally not critical to the plant's survival.
I'm not used to any kind of 'gravel' substrate this stratum is just trying my patience haha. I have noticed melting, and it worried me at first because I've found crypts to be the most adaptable of all my plants. Good to know this isn't something to worry my head over.I have two tanks with Fluval Stratum, they are an absolute nightmare to plant and keep planted. I wish I'd never bought the stuff as plants float out of it if you give them the slightest nudge! It was expensive though so I need to use it up.
Be aware that crypts might well melt when replanted- this would not be because you trimmed the roots, it often happens due to a change in environment. If you leave them alone, even if they look dead, they should grow back from the taproot (this is the thickest root coming directly out of the plant).
I planted nine crypts in my planted tank. Eight of those melted away to nothing, and of those eight, seven grew back and are looking wonderful now. Patience is key here.
Thanks for the tip! That sounds fairly useful, I'll try that!I love crypts and keep a whole huge variety of them. They handle root trimming well. If I move them I cut off almost all the "hair" type roots and will trim back the main ones to about 2/3 the length of the largest part of the plant.
Also really like stratum and my trick with stratum is to tie a portion of the roots to a small stone before planting. I prefer cotton thread but have used fishing line. It keeps the plants from moving or floating up until the roots are established but doesn't restrict them at all.