Issue with daffodils

in_my_wellies

I think they are very sensitive to conditions. Late last spring I removed a 53 year old azalea which suddenly died from the left side of a 9' x 2' bed. It left a large hole which I filled with new compost before digging the whole bed and replanting. In September I planted three bags of mixed daffodils from Wilko. The bed is sunny from midday until dusk.
Those on the left in the new compost have all done well, those in the centre are just about OK but those on the right have just two flowers.
I shall be replacing the soil on the right hand side before planting again. (Summer bedding and the bluebells haven't shown this growth difference)