Rose Care tips for seattle gardeners
One of the most widely planted of all shrubs, Rosa species and cultivars are easy to grow and immensely rewarding. This information sheet provides simple, basic procedures for rose gardening success.
PREPARING THE PLANTS
BARE ROOT ROSES should have any broken roots pruned back and the root ball immersed in lukewarm water for 12 to 24 hours prior to planting.
POTTED ROSES should have the tangled mass of feeder roots gently loosened from the soil ball. If the mass is severely pot bound, use a sharp knife to score the root mass, then spread them gently apart. Failure to loosen these roots may cause the plants to girdle themselves.
SOIL PREPARATION & PLANTING
CHOOSE A LOCATION that receives full sun and adequate air circulation, away from competing tree roots. Avoid crowding plants to insure best bloom and help prevent disease.
DIG THE HOLE twice as wide as the root ball and deep enough to ensure that the graft or bud union at the base of the plant remains above ground level after backfilling.
BACKFILL THE HOLE using a mixture of 1 part Gardner & Bloome® Soil Building Conditioner or EB Stone® Planting Compost to 4 parts native soil. Do not use potting soils.
WATER & FERTILIZATION
WATER ROSES immediately after planting using a transplant solution if desired. Water roses twice a week the first summer, and once or twice a week thereafter. Avoid overhead watering to help prevent disease and to protect blossoms.
FERTILIZE ROSES using a balanced fertilizer such as Espoma® Rose-tone or Dr. Earth® Rose and Flower Fertilizer.
ANNUAL PRUNING should be done at about the end of February in western Washington to avoid the risk of late frosts damaging new growth. After early pruning, leaf junctures will begin to swell on the stems, allowing more judicious pruning for shape and effect.
A GOOD RULE OF THUMB when pruning roses is to leave no wood on the bush that is thinner than a pencil. Removing any twiggy, weak or dead wood will help produce more abundant blooms.
LIGHT PRUNING with bushes left tall makes next season's bloom short-stemmed but profuse.
MODERATE PRUNING leaves five to ten, 1 - 4 foot long canes per bush. Generally about half of each cane is pruned back, producing a fine display of bloom with some long-stemmed.
SEVERE PRUNING which leaves only four canes per bush, each cut lower than 1 foot long, provides the best winter freeze protection and produces the longest-stemmed blooms.
Because of our long, cool and wet springs, roses often will contract fungal diseases. It is very difficult, if not impossible to eradicate a fungal disease outbreak during the spring and summer, therefore, it is best to prevent the plant from getting the disease in the first place.
GOOD SANITATION practices like removing all the dead leaves and dead twigs every winter from the previous year are the first step to prevention.
KEEP THE FOLIAGE DRY during the warm seasons. Disease can only get a foot hold when the foliage is wet and warm. Luckily we don't get much precipitation when the weather is warm.
DORMANT SPRAYS can kill disease spores and insects that are already present.
FUNGICIDES can kill disease spores that are present and they can prevent spores from germinating over a period of time.
REMOVE AND DESTROY all affected leaves. Do not compost or recycle diseased leaves.
FUNGICIDES registered for roses will not cure affected leaves, but can be used to help prevent healthy leaves from becoming infected.
INSPECT PLANTS OFTEN as early detection of infestation is the best antidote.
REMOVE APHIDS from affected leaves or gently smash them between thumb and forefinger, being careful not to bruise leaves or damage flower buds.
WASH OFF PLANTS with a gentle stream of water from the hose. Avoid using spray nozzles which can damage buds and tear leaves and blossoms.
INSECTICIDAL SOAPS listed as safe for use on roses may be used. Follow label directions.
CHEMICAL INSECTICIDES are numerous and effective. Follow label instructions.