The best time to prune what are termed "Garden roses" is immediately
after flowering, which is generally about the middle of June. Cut out
all old exhausted wood, and where it is too thick and crowded,
shortening those shoots which have flowered to a good fresh strong eye,
or bud, accompanied with a healthy leaf, but leaving untouched such
shoots as are still in a growing state, except where they are becoming
irregular. Such should be cut to the desired shape. There is not a
better period of the year for puting these bushes in handsome order,
which ought to be studied. All wood that grows after this pruning will
ripen perfectly and produce fine flowers next year.
Our reasons for doing so at this period are these: The points of the
shoots of the more delicate sorts of roses are very apt to die when
pruned in winter or spring; hence the consequences of this evil are
avoided. The stronger the wood of roses is made to grow, the flowers
will be the larger and more profuse, and this effect is but produced by
cutting out the old and superfluous wood; at least it prevents any loss
of vegetative power, which ought always to be considered.