featuring Claude Smith
My roses lose their leaves after blooming – what am I doing wrong?
The first thing that comes to mind is heat stress. Roses usually bloom in late June, early July and that’s when the temperature starts to climb. They will need lots of water to get them through the heat of the summer. The best way to check if they’re getting enough water is to push your finger at least three inches into the soil to check for moisture. If the soil is dry, it’s time to water. Make sure you water at the soil level and not overhead.
The loss of leaves could also be caused by insects. Look closely at your plants for signs of soft bodied aphids or webs from spider mites. You can help to control aphids with a jet of water to knock them off, then spraying them with insecticidal soap. It usually takes a few applications to control them. Spider mites like a dry environment, so watering is crucial. Planting chives, marigolds, cilantro around your roses will attract beneficial insects and help reduce the population of the harmful insects.
Other causes for leaf drop could be certain fungi such as black spot, rust or powdery mildew. Cleaning up the dead leaves to suppress the spread is an important step in dealing with fungi. Powdery mildew especially likes humidity, so leaving some space between plants is crucial for good air circulation.