Now that it's mid-February, our pruning and planting chores are - or should be - behind us!
Be sure that all of last year's leaves have been stripped off the remaining canes, raked from the ground and disposed of in the trash, because they may harbor mildew spores and insect eggs that could re-emerge to cause havoc with new foliage and buds.
Inspect the tops of pruned canes for signs of a hole or sawdust, which would indicate that cane borers are at work tunneling down through the tissue to deposit eggs. Re-cut below any holes you may see and apply Elmer's wood glue to every pruning cut to seal pests out and keep moisture in.
It's time to begin fertilizing again, but always after first watering well. To improve soil chemistry and increase the exchange capacity of the soil before beginning fertilization, toss a cup of Epsom salts (magnesium sulfate) around each mature bush and water well. Although there are good time-release granule products such as Organo (4-12-4), Arizona's Best (9-11-3) and dried poultry waste (5-8-5) to give your roses a nice boost in vigor, it's hard to improve on Magnum-Grow (8-10-8) available at Berridge Nursery on Camelback Road. This is a quick-acting, water-soluble concentrate specifically formulated for roses by a past president of the American Rose Society.
Magnum-Grow's greenish-blue crystals resemble Miracle-Gro for Roses, another good feeding choice. Mix 1 tablespoon per gallon of water and apply 2 gallons per plant for mature large roses planted in the ground or half strength for miniatures and potted large roses. Stirring the crystals in a little hot water first will dissolve them quickly.
The three numbers mentioned above and that you see on fertilizer packages
stand for the primary nutrients NPK. The "N" is nitrogen for cell growth, production of strong canes and healthy green foliage, "P" is phosphorus for
stimulating root growth and flower production, and "K" is potassium to enhance bloom size and color and acts like a vitamin to help the plant through stressful times.
Chemical fertilizers should be balanced with plenty of humus in the soil.
This can be achieved by applying dried poultry waste and topping with several inches of aged horse (not steer) manure as mulch. As the manure breaks down, it adds organic material to the soil. Rose growers here in the Valley are indeed fortunate that there are so many horses in the area providing an endless (and usually free) supply of mulch for our roses! A thick layer of mulch is especially important throughout the stressful heat of summer, whether animal-generated or a bagged commercial mix available at garden centers.
Along with beginning a feeding program, it's important to water regularly and deeply. Although it's been a mild winter, watering well once or twice a week should suffice for bushes in the ground until temperatures increase, but plants in pots need to be watered more frequently as roots must never become dry.
Although this month our newly pruned rose beds resemble a collection of
forlorn sticks, they are already beginning to leaf out nicely and we can
look forward to the glorious blooms in April that will reward our efforts!