Hi, are there many stems on the plants? most roses are grafted onto briar rootstock and if the shoots are coming from below the graft they wont flower, at least not the flower you want! they,re suckers from the briar, usually there are 5 leaflets on a rose leaf,and 7 on any suckers,{although not always}, if they,re coming from below the graft or below soil level cut them off as close as possible to the point of origin, and feed them with a specialist rose feed. regareds derekm

Is it a bush or a floribunda? you get more roses with floribundas. How are you pruning/dead heading as this can make a difference, as can growing conditions. For a good answer you need to supply more information.

Make sure that they are getting at least 4 hours of direct sun a day, feed them regularly, and water them deeply and regularly (if possible) in dry spells. Some of the old roses, some shrub roses, and some ramblers and climbers only bloom on second year wood, so if they are getting pruned harde in early spring, blooms will be sparse to non-existent, and those varieties normally don't bloom much from midsummer on, anyway.