In late spring, when the soil has thawed and a hard freeze is no longer expected, carefully remove soil mounds from established plants so as not to damage any shoots that have begun growth. Wash away the last of the soil from the centre of the bush with a gentle stream of water. Clear away any pruned material and dead leaves left from last fall.
In the spring, newly planted roses should be cut back quite severely, leaving only three strong canes 10-12 cm (4-5 in) long. This encourages production of strong new growth and canes. Established rose bushes are pruned after the soil mounds have been removed in the spring when canes show signs of growth, usually April or when the forsythia is in bloom in your area.
Cut out any dead or diseased shoots to ground level. The canes on Shrub roses should be cut back to green, live wood and then the bush can be shaped as cosmetically desired.
Climbers: If allowed to grow vertically, the canes on climbing roses will only produce flowers at the top. Training the canes in an arched, horizontal form will greatly increase the number of flowers produced from buds all along the wood. It may also encourage long laterals to grow from the established canes, creating a larger bush with many more blooms. In the spring remove all the dead wood and then prune all the small lateral branches down to 2 or 3 buds
On other roses remove weak, twiggy and crossing shoots to their point of origin, leaving only 3-6 healthy canes of pencil thickness or better. Cut these back to live wood, as indicated by white pith. Pruning cuts should be made with sharp shears, about 5mm above an outward facing bud.