I think you need to wait until you see them actively growing and becoming small plants in their own right, they obvioudly need a good root system.......keep tending them, it could take a few months, hopefully a warm spring will bring them on

in the garden they take about 3-6 weeks to make healthy roots. as long you have a bit of the stem with a leaf coming from it buried it will root. the 'root buds' for want of a better word [meristem tissue to be more botanical] are behind the leaf where it joins the stem.

They are thugs in my garden and I can't get rid of the so and so's. I am continually pulling the trailers out - to no avail. Their only saving grace is their pretty flowers. They have even started to grow down into a drain.

Thank you all so much they have got leaves growing from the section after which it is pegged down in the compost so I assume they are now growing

tug at them gently if they don't pull up then yes they have roots. if they pull up then they don't, so re-bury. as the tips are still attached to the parent plant they will get their nourishment from that and that's why they are growing.