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. Here are the basics to set you up for rose gardening success!

SOIL PREPARATION & PLANTING

CHOOSE A LOCATION that receives maximum 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 equal to its depth. Sprinkle rose fertilizer per label directions along the bottom of the planting hole.

REMOVE PLANT FROM THE POT carefully, to avoid breaking up the root ball if possible. If roots are tightly wound or tangled around the ball, try to gently loosen their outer layer. You can use a sharp knife to make a few cuts through the mass about 1 inch deep, and gently splay the roots out.

SET THE PLANT in the hole at a depth enough to ensure that the graft on the main trunk remains a couple of inches above ground level after filling the hole.

FILL THE HOLE using a mixture of 1 part Gardner & Bloome® Soil Building Conditioner or EB Stone® Planting Compost to 4 parts native soil. Water immediately and thoroughly. If there is significant settling, add more soil to level it off.

MULCH THE PLANTED AREA with 2-3 inches of compost or fine mulch, to preserve moisture and minimize weeds. Keep mulch a few inches away from any contact with the trunk.

WATER & FERTILIZATION

Proper watering and fertilizing can make a dramatic difference in a rose’s health and performance!

WATER ROSES by thoroughly watering the soil over the root zone, twice a week over the first summer, and once or twice a week thereafter (variable with the weather). Avoid watering the foliage to help prevent disease and protect flowers.

FERTILIZE ROSES using a balanced fertilizer such as Espoma® Rose-tone or Dr. Earth® Rose and Flower Fertilizer. For established roses, dig a trench 1-2 inches deep around the drip line of the rose. Sprinkle fertilizer per label directions, and (optional) 2-3 cups Earthworm Castings, rake or smooth it in, and water well.

PRUNING ROSES

LATE WINTER: The annual major pruning is ideally done around the end of February in western Washington. Pruning earlier in winter can increase the risk of dieback from hard freezes.

PRUNING HYBRID ROSES IN LATE WINTER: a good rule of thumb is to leave no wood on the bush that is thinner than a pencil (except on some fine-branched varieties). Remove any twiggy, weak or dead wood.

LIGHT pruning with bushes left tall makes next season's bloom short-stemmed but profuse.

MODERATE pruning leaves five to ten canes per bush, about 1- to 4-feet-high. This tends to produce a fine display of blooms with some long-stemmed.

HARD pruning leaves only four canes per bush, all shorter than 1 foot. This allows easier covering if winter freeze protection is needed, and produces the longest-stemmed blooms.

LATE SPRING/SUMMER: Cut blooms for bouquets, and fine tune as needed, including deadheading spent blooms, thinning out crowded branches, and heading back any aggressive outer shoots.

LATE FALL: Head back lightly to clean up the look and remove old flowers and hips (fruits) unless they are particularly ornamental or you are leaving them for wildlife. Canes on hybrids may be cut back to 3-4 feet high.

DISEASE PREVENTION & CONTROL

Because of our long, cool, wet springs, many roses are susceptible to fungal diseases such as black spot and powdery mildew, which can appear during the spring and summer. Some rose varieties are more resistant, but prevention is the best defense. The following steps can help:

GOOD SANITATION practices like removing all the dead leaves and dead twigs every winter, and as you find them over the summer. Dispose of any infected leaves (do not home compost them). Mulch the ground to cover any remaining spores.

AVOID WATERING FOLIAGE during the warm seasons. Disease can get a foothold when the foliage is wet and warm. But keep watering the root zone, as drought stress can also enable disease.

FUNGICIDES can prevent healthy leaves from becoming infected, but will not cure those already infected. Sprays work externally, but systemic fungicides work internally, protecting plants longer.

INSECT PREVENTION & CONTROL

Insects are generally not a major threat to roses in our region. Aphids are the most common issue although mites, thrips, and various beetles can sometimes attack. If you find bugs but no obvious damage, get a positive identification — many insects are beneficial.

INSPECT PLANTS OFTEN as early detection is the best defense.

GOOD SANITATION (as mentioned above for diseases).

APHIDS can appear on tender, new buds and stems, and under leaves. The first response is to squash them or wash them off with a stream of water, perhaps adding some mild dish soap. Avoid using spray nozzles which can damage buds or tear leaves and blossoms. Spray early in the day, so that leaves don’t remain wet for long.

INSECTICIDAL SOAPS or CHEMICAL INSECTICIDES can be effective for heavy or persistent infestations. Systemic insecticides work internally, protecting plants longer. Always follow label instructions.