Thanks everyone.
I use a mixture of chicken & caw manure,compost, perlite and potting soil.
The cultivars I have and not growing are: Lampiera ( I have two one is growing and one doesn't and are in the same potting mix), Bourgeasotte grise, St Anthony, Col de Dame Noir, Gross Montreause de Lipari, Blue Celeste( one growing ,one not).Hope my spelling is not that bad :)
I did not start to fertilize them till recently and I used a very weak solution.
Unfortunately I am leaving town for a month and my teenager son will be responsible for taking care of my plants. I wanted to see them putting new gross before I leave.
May be I'll re-pot them and see what happen.
Pat.