hi possibly because there seems to be over crowded and need splitting up i think they are root bound if i was you i would be planting these in the garden asap others will tell you more.good luck.

Thank you

If there are more than one plant in the pot they have been left too long before repotting and it will be difficult to separate them without damaging the roots. If there is just one plant it needs potting on or planting out as Kenny says.

Also, in my experience, most of the large-leaved hybrids are naturally semi-trailing.

Don't bother trying to separate all the plants growing together there. Trying to tease apart the roots will kill everything. Just pot-on/plant out the entire clump. Use a tiny pair or scissors to snip off all but the strongest plant in the clump. Let the rest wither away.

Thank you all so much. I did an experiment, I put 1 into some pots and 2 into other pots but they all seem to be inclined to trail. Is it in their nature to trail?

As I said, that is my experience.

Thanks tugbrethil