If planting in winter, choose a frost-free spell when the soil is not frozen. Roses are quite deep-rooted plants so dig a deep hole roughly twice as wide as the plant's roots and mix in a generous amount of composted organic matter. A top-dressing of a general purpose fertiliser can be worked into the surrounding soil and we also recommend using Rose Rootgrow at this stage to encourage better root development. This is particularly important when planting into a bed where roses have previously been grown as Rose Rootgrow is said to combat rose sickness (aka replant disease).
Remove the plants from their pots and gently spread out the roots before placing them in the centre of the hole. Try to ensure that the 'bud union' (the point where the cultivated rose has been grafted onto the rootstock, and from where the shoots emerge) is at soil level. You can judge this quite easily by laying something flat, like a spade handle or bamboo cane, across the top of the hole. When they are at the right height, back-fill the hole, firming the soil down gently before watering the plant well.
Water generously until well established, and apply a specialist rose fertiliser (following the manufacturer's instructions) each spring. They will also benefit from a generous mulch of composted farmyard manure in spring, but make sure this is kept away from the stems.
In late winter, pop on a pair of tough gloves and remove dead, damaged, diseased or congested branches completely. Then cut back vigorous new shoots by up to a third, and shorten strong side shoots to within two or three buds of the main stems. If the centre of the shrub is becoming congested, remove one or two of the older stems to their base. After the first flush of flowers has faded, prompt deadheading will encourage more flowers to form.