Flea beetles or slugs could be eating violets
Question: What is eating small holes in my Rosina Viola?
Flea beetles are tiny black beetles that eat small holes in the leaves of a variety of plants, including Rosina violas, also known as sweet Rosina violets. Healthy established plants can usually tolerate damage caused by small populations of this pest.
Managing weeds, removing plant debris in fall where these pests overwinter and planting a trap crop of radishes that attracts the flea beetles and can be sprayed with an organic pesticide like pyrethrum or spinosad are several management strategies.
Slugs are another possibility. They eat larger irregular holes in the leaves of plants at night and hide during the day. Sink a shallow container filled with beer into the soil near the plants. The slugs will crawl inside and die. Or use one of the organic slug controls with iron phosphate as the active ingredient. Always read and follow label directions whenever using any chemical, organic, natural or synthetic.
Q: I have a yellow braided hibiscus with an infestation of tiny white flying insects. I have sprayed with several insecticides with no results. What do you recommend to rid this plant of the insects, so when I bring it in in several months they are not in the house? The bugs were first noticed in the spring in the house prior to placing it outdoors.
Whiteflies are a common pest on houseplants that summer outdoors. These insects cannot survive our winters but often hitch a ride into our homes when the plants move back indoors for winter. Plants can usually tolerate the whitefly damage when growing outdoors in the summer. Once they move inside where the growing conditions are less than ideal, the whiteflies thrive and their feeding increases stress on the already stressed indoor plants.
Try treating with a lightweight horticulture oil like Summit Year Round Spray oil. This kills all stages of the insect. It is a contact insecticide, so it kills the eggs, larvae and adults it touches. Repeat applications will be needed. In the fall isolate your plants for several weeks, monitor for this and other pests, and treat as needed before adding them to your indoor plant collection. Yellow sticky traps can also help you monitor and manage these insects on your indoor plants.
Q: I planted a rhododendron last spring, which bloomed and formed next year’s buds. However, it did not flower this spring but did get new leaves. It receives sufficient sunlight. Any ideas why it did not flower?
As you know rhododendrons form their flowerbeds the summer prior to spring flowering. The large plump buds at the tips of the stems are flower buds, while the smaller buds along the stems develop into leaves. If your plant did develop flower buds, our fluctuating cold and hot spring temperatures may have damaged these buds, preventing them from blooming. If your plant only had smaller buds, it did not form flower buds, explaining the absence of flowers.
New plantings of flowering shrubs are often in bloom when we purchase them but fail to flower the next year or two. Newly planted flowering shrubs often expend their energy establishing roots instead of flowers. This is good for the longevity of the plant but annoying to the gardener. Once the plant is established, flowering should begin. In the meantime avoid high nitrogen fertilizers that promote leaf and stem growth and can interfere with flowering.
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