How much should I cut off my shrubs and rose bushes now?

Question

I heard 2/3 is that right?

This is their 2nd year! The shrubs are very old but not too healthy.

Answer 1

On climbing roses cut out the old canes now. T. roses we cut out only small twigs and brances that are crossing over or growing to the center of the plant. Trim back the tips to encourance new growth, you want to encourse new flowering stems that will grow out and not in. fertilize and remove all dead matter around the bottom, there are cheap books out there used and you might consider getting one for future reference. Is this your first year of growing roses?

Answer 2

The class of rose and the time of year it blooms influence the type and amount of pruning.
Roses like hybrid teas, floribundas, patios, & miniatures flower best on new wood. To renew the wood each year means 1/2 - 2/3 of the height is cut off and removing small or weak canes. Leave 3-5 canes with out facing buds. Note buds grow in a spiral around the cane so just look up and down each cane til all the out facing buds are located. Then cut 1/4 inch above the bud such that the cut slopes down, away from the bud.
Pruning is done to accomplish several tasks.
Remove dead or diseased wood
Increase air circulation to prevent disease.
Shape the plant so it appears less tangled while still growing new flowering wood.
Pruning after the forsythia blooms is safe in most areas.
Remove any cane from last year that is no more than a pencil in width.
Since you said you were told 2/3 of the height it sounds like your plant is not a shrub rose or a non-remontant rose. These bloom on old and new wood and are pruned differently from hybrid teas.
Shrub roses are best pruned to open them so they are less tangled yet have mature wood (one winter old) but not aged wood. In spring remove 1/3 of the oldest canes. This keeps the shrub producing new growth to replace aging canes. These canes can be shortened to fit a space.
David Austin recommends;
SPREADING TYPES: Remove about 1/3 of the length of all the stems to an outward facing bud.
ARCHING: Remove 1/5 of each stem to maintain the plants shape.
BUSHY: Remove 1/3 of each stem to a bud. Remove weak spindly growth.
UPRIGHT: Prune hard removing half of each stem to an outward bud.