I have 4 10 year old hydrangea plants that have become very unwell. I have identified that in the summer they were infested with white scale. I treated them with Provanto Smart bug Killer as instructed several times but it didn’t work. Buds are beginning to grow on the damaged plants and I am stressed that it is going to happen again. I don’t think they will survive another year. These plants mean the world to me so I don’t want to remove them. Is there anything I can do? Please help!!
White scale on hydrangeas
- Thread starter Preecem
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When you say white scale do you mean soft bodied scale or hard scale? Pictures would also help. You may not be using the correct insecticide.
Hi, I didn’t take any pictures in the summer but there are a few scales still on the plant even though it’s winter. I have attached this photo. I have also attached a pic of what they did look like in the summer from the Internet. There is a black sticky substance around the base of the plants, if that helps.
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You have both hard and soft scale. The soft scale is the immature hard scale. The hard scale is permanently attached to the plant and when it is killed it does NOT fall off of the plant. The plant sheds the dead hard scale with its growth, forcing the scale off of the plant. Spray with FRESH Neem Oil every 5-7 days for three applications. This will kill all of the scale but the hard scale will stay on the plant until the plant grows enough to force it off. The black stuff is the honeydew from the soft scale. The insecticide you are using is good for soft scale but not very effective against hard scale. The best way to kill hard scale insects is to smother them and the oil in the neem does this.
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Your plant is starting to bud out. I would start now while the leaves are gone so as to make it easier to cover the plant with the spray.
I'm sorry to hear that your hydrangea plants are unwell. It sounds like the white scale infestation has caused significant damage to the plants. If the Provanto Smart Bug Killer did not work, you may want to try a different insecticide that is specifically formulated for scale insects.
One option is to use a horticultural oil spray, which suffocates and kills the insects. You can mix the oil spray according to the instructions on the package and apply it to the plants, making sure to coat all surfaces of the leaves and stems. Repeat the application according to the instructions, as needed.
Another option is to use a systemic insecticide, which is absorbed by the plant and kills the insects when they feed on it. However, systemic insecticides can be harmful to beneficial insects, so use them sparingly and follow the instructions carefully.
In addition to treating the scale infestation, you may want to make sure that your hydrangeas are getting the right amount of water and nutrients. Hydrangeas prefer moist, well-drained soil and benefit from regular fertilization. You can also prune away any dead or damaged branches to encourage new growth.
If your plants do not recover, you may need to consider replacing them. However, with proper care and treatment, it is possible to save them. Good luck!
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