Start with the Soil
The healthier the soil, the healthier the plant. Even though you can’t see what’s going on in your soil, there is actually a whole world in there: tiny, living organisms plus decaying plant matter and minerals. Good soil is the essential foundation for your plants. It provides nutrients that are required for plant growth and it holds an adequate amount of moisture to sustain your plants between waterings. An organic potting mix from the nursery or garden center is ideal for your containers because it is specially formulated to drain quickly and prevent soggy, water-logged soil. Each season replace about 1/3-1/2 of the soil in the container with fresh potting mix, as continual watering will leach nutrients. Healthy soil from the start will enable your roses to better ward off pests and diseases.
Non-Toxic Treatments for Pests and Diseases
There are many people who wouldn’t dream of not spraying their roses. But unless you are growing roses for competition, a few damaged leaves seems a small price to pay to keep harsh, toxic chemicals out of our waterways (which is where all your run-off from watering ends up). And today, there are an increasing number of effective alternatives to chemicals.
When gardening organically, heading a problem off or spotting it early are the best ways to ensure that you don’t end up with an infestation that’s out of control. Never was there a better case for prevention. Good horticultural practices, such as giving your rose sufficient sun (5+ hours per day) and water, providing good air circulation, cleaning up dropped leaves, disinfecting garden tools after each use and buying disease-resistant roses in the first place, are the first steps to take.
There are 3 rose diseases that are most common: black spot, powdery mildew and rust. These are all fungal diseases which can be spread by the wind, improper watering, insects or even contaminated garden tools.
- Powdery Mildew appears as a whitish powdery substance covering the tops of the youngest leaves. It likes cool, humid evenings and warm, dry days. It can overwinter in diseased leaves and buds, whether still on the plant or on the ground. Making sure your rose has good air circulation and not working around the bush when the leaves are wet will help control this disease. Try not to overhead water your roses, particularly late in the day, because this will leave them with wet leaves as the temperature cools down in the evening. You can also spray the leaves with an application of baking soda (3 teaspoons) combined with horticultural oil (2 ½ tablespoons in a gallon of water).
