You'll be swell, you'll be great,
Gonna have the whole world on a plate,
Starting here, starting now,
Honey everything's coming up roses.
— Stephen Sondheim, “Everything’s Coming Up Roses,” 1959
My rose bushes are blooming profusely right now, inspiring me to belt out this verse from Ethel Merman’s signature song, “Everything’s Coming Up Roses," which was written for the Broadway play “Gypsy: A Musical Fable.”
“Gypsy” has enjoyed numerous renditions over the years; similarly, I’m looking forward to repeat performances from my garden roses, regarded by many as the queen of all flowers. However, keeping roses happy and healthy during hot summer months in the Rogue Valley can be a bit tricky. Here are a few things I’ve learned to help all of us rose enthusiasts ensure that the show does, indeed, go on.
Roses need a consistent watering schedule throughout the summer to keep the soil evenly moist but not wet. Use drip irrigation or soaker hoses to water deeply twice a week, and even more often during our scorcher weeks. Thirsty rose bushes will each gulp about six gallons of water per week during July and August. Although certainly not a suitable plant for xeriscapes, roses do become more drought tolerant after three to four years when the roots are well-established.
Keep in mind that roses have deep roots, so use a 24-inch moisture meter to ensure the water is draining to root level. Exactly how much watering is needed depends on the weather and the type of soil you have — sandier loams will drain faster, and soil with more clay will hold water for longer.
The fact that roses don’t like high temperatures can become a thorny issue during our hot summers, considering they also need plenty of sunshine. The ideal location for roses is in beds and borders that provide some shelter from the wind and receive at least six hours of sun daily, preferably during the morning hours. There’s no such thing as a truly heat-resistant rose, although some varieties will tolerate a bit more heat than others (see my blog this week at mailtribune.com/blogs).
Mulching benefits roses by helping to keep the soil cooler and moister, and by reducing competition with weeds. I add compost in the spring and then top off with bark chips about 3 inches deep (dried grass and straw may also be used). Leave off mulching a few inches around the base of the plant. Also, be aware that the downside of mulching is that it creates an inviting habitat for insects — beneficial and otherwise.
Compost added to garden soil in the spring will decompose slowly, providing nutrients throughout the summertime for our heavy-feeding roses as long as the roots get enough moisture to make the nutrients available to the plant. Some gardeners mix alfalfa pellets and/or steamed bone meal to the compost; others use time-released granular fertilizer.
Repeat-blooming roses also benefit from an additional feeding right about this time, as the first flush of flowers is beginning to fade. Some gardeners recommend using a balanced fertilizer (such as 10-10-10), but I prefer a fertilizer that is higher in phosphorous (promotes budding) and lower in nitrogen (promotes foliage); lusher foliage is more susceptible to heat and pests. When fertilizing, water thoroughly first, add fertilizer, then water again. Avoid fertilizing during the heat of the day, and stop fertilizing by the end of September to allow roses to prepare for dormancy.
Some gardeners fertilize their roses every four to six weeks by using a chemical (processed) solution at half-strength; others apply an organic fertilizer only once for slow-release feeding. One recipe for an organic fertilizer is: 2 T. powdered fish, 1 tsp. kelp extract; 1 T. Epsom salts, 2 T. apple cider vinegar, 2 T. molasses and 3 cups water. Mix thoroughly, pour in a 2-gallon watering can and add water to the top. Apply as a foliar feed and to the plant’s root zone.
Check out this week’s Literary Gardener blog (http://blogs.esouthernoregon.com/theliterarygardener/) for pictures of my roses, tips for deadheading roses, what to do about pests that are common to roses, and varieties of roses that don’t mind some shade and those with fewer thorns.
— Rhonda Nowak is a Rogue Valley gardener, teacher and writer. Email her at firstname.lastname@example.org.