This time of year, you may notice a white, powdery looking growth on fruit, vegetable plants or ornamental plants in your garden. What is it? It could be powdery mildew.
Powdery mildew is caused by several different fungi that may attack plant leaf surfaces, shoots, fruits, and flowers. There are several species of powdery mildew; all are spread by wind and thrive in shady areas when temperatures are between 60-80 °F. The fungi attack both new and old foliage, and can be a problem on certain plants. The disease usually occurs first on new leaves, before spreading to older parts of the plant. This is why over fertilizing worsens powdery mildew.
Ornamental Plants
Many woody and herbaceous...
Controlling unwanted trees, shrubs, and woody perennial grasses can be difficult in landscapes, gardens, and natural areas. These troublesome woody plants often resprout after being cut back, and the resprouting shoots can outnumber the original plants. Some woody weed plants are natives but in certain settings can create fire hazards and become problematic to human health and movement.
So how can you manage plants like ivy, bamboo, and poison oak?
A new version of Pest Notes: Woody Weed Invaders, authored by UC Davis plant scientists Joseph DiTomaso and Guy Kyser, is now available online and in print. Use this guide to find answers to the...
- Author: Belinda Jane Messenger-Sikes
If you subscribe to our Pests in the Landscape blog, you'll notice that we frequently post updates about Asian citrus psyllid (ACP) and huanglongbing (HLB). Educate yourself about ACP and HLB so you can help prevent its spread. Here are a few things you can do:
- Read the Pest Note: Asian Citrus Psyllid and Huanglongbing to learn how to identify the psyllid, host plants, and what you can do.
- Visit this Distribution of ACP/HLB website to find out if ACP/HLB has been found in your area.
- Watch this
Invasive plants are weeds that infest natural ecosystems, rangelands and pasture. They can cause dramatic ecological changes that affect both plant and animal communities. Once established, invasive plants are difficult to eradicate.
In California, exotic plants were originally introduced by humans who planned to use them for ornamental or aquarium use, or for use as forage, food, fiber, medicinal or soil stabilization purposes. In some cases, the unintended outcome has been plants that have become invasive.
Some invasive plants are still for sale at retail nursery and garden centers. Some examples of available invasive plant species include pampasgrass (