Q: Can you simplify rose pruning for me? Most books make it seem difficult, and most of my friends don't know too much about it, either . --R.S., Baldwin Park A: Staff members at the Los Angeles State and County Arboretum as well as at Descanso Gardens and South Coast Botanic Gardens say that questions about pruning roses are among those most frequently asked. They advise pruning in February when roses are at their most dormant stage.
Begin by pruning away dead twigs and all weak or spindly stems. Stems smaller in diameter than than a pencil should be removed with cuts made just above healthy, outward-facing buds. This will result in a vase-shaped bush, open in the center so air can circulate.
All other canes should be cut back by one-third. Cuts on larger stems should be sealed with a pruning compound to prevent damage by pests or disease.
In the case of climbing roses, most long canes should be retained and secondary branches left with two or three buds on each. Descanso Gardens holds an annual pruning demonstration each year , as does Rose Hills and the Exposition Park Rose Garden.