Plants that are regenerated, cloned and even grown from seed will need to be pruned at some point to encourage the plant to produce as much as possible and remain healthy. Pruning the lower limbs creates more air-flow under the plants in an indoor situation and creates cuttings for cloning. It also forces the plant effort to the top limbs that get the most light, maximizing yields.
Plants that are regenerated need to have minor growth clipped so that the main regenerated growth will get all the plant energy. This means that once the plant has started to regenerate lots of growth, the lower limbs that will be shaded or are not robust should go. The growth must be thinned on top branches such that only the most robust growth is allowed to remain.
Once nice aspect of regenerating plants is that some small buds left on the plant in anticipation of regeneration will not sprout new growth and may be collected for smoke. The plant may provide much smokable material if it is caught before all the old flowers dry up and die with the new vegatative growth occuring.
Try to trim a regenerated plant twice. Once as it is starting to regenerate, collect any bud that is not sprouting with new growth and smoke it. Then later, prune again to take lower clippings to clone and thin the upper growth so that larger buds will be produced.
If a regenerated plant is not pruned at all, the resulting plant is very stemmy, does not create large buds and the total yield will be significantly reduced.
Article written 2004 and featured on Grow-Marijuana-Seeds.com