Around the Yard
Things to do this week:
* Spray for rose “slugs.” The hungry larvae of a sawfly, called “rose slugs” by gardeners, can do severe damage to rose leaves, peppering them with small holes and scars. They are hard to control unless you start early in the year. No matter what you use, one application will not do the trick. Begin now and spray every few weeks during spring. Then keep a watchful eye in summer, spraying when the first signs of damage appear.
There are various chemicals that will control them, but the safest product is a horticultural oil that smothers, not poisons, the larvae. Make sure you get the kind that can be used in summer and follow label directions for roses, making sure you spray the undersides of leaves, where rose slugs hang out.
* Feed camellias. This is the time to fertilize camellias--right after they finish blooming--and the easy way is to use cottonseed meal, a naturally acidic organic fertilizer that is also a byproduct of cotton farming. This is what Descanso Gardens in La Canada Flintridge uses on its thousands of camellias, which are fed twice a year, in spring and early summer (but newly planted bushes aren’t fertilized at all). Sometimes Descanso mixes one part blood meal with four parts cottonseed for that first feeding.
You’ll find bags of cottonseed meal at nurseries. Scatter it all around the plants, following label directions, and let rain or irrigation carry it into the soil. You can also fertilize azaleas with cottonseed meal.
* Turn hydrangeas blue. This is the time to apply aluminum sulfate to container-bound hydrangeas or those that grow in the ground. The aluminum sulfate acidifies the soil, which turns blooms blue, and must be applied early, before flowers form. Aluminum sulfate can be found at nurseries, often packaged just for hydrangeas.
Remember, not all hydrangeas turn blue. If the one you bought wasn’t blue to begin with, it’s probably a pink or white variety and will not turn blue. But if you don’t remember or know, it won’t hurt to apply aluminum sulfate.
