I don't have the pink ones. Are you sure it is Pink. My rose Jasmin bud looks pink on the outside and when it open it is white. Also I have young Grand duke and some one posted that he has on his grand duke white and pink flowers. I hope I can get the same.
My Jasmin are planted in pots and that is what I use for soil 25% soil-25% perlite-25% Humus-25% Moss. The moss retain moisture for the roots, the perlite make the soil light and easy for the root to penetrate and the HUMUS is the height form of Organic fertilizer. The only thing wrong with using Pots is you have re-pot every 2 or three year. I have to use pots because my Winter is cruelly cold and I Winter all my Plants inside the House.

Jasminum polyanthus blooms once.