Scale on plants sounds like and looks like a plant disease, but the term “scale” actually refers to an infestation by any one of over 8,000 species of tiny, sap-sucking insects. Scale insects typically adhere to the stems, branches, and sometimes leaves of plants to feed on sap. They have a shell-like bump appearance, which makes it easy to mistake them for a fungal or bacterial disease. Though, the treatment of scale on plants is much different than the treatment for plant diseases, so it is essential to know the difference.
Below, learn about how to identify, combat, and control scale insects on plants both inside and outside.
As an avid gardener and plant enthusiast, I’m always on the lookout for ways to keep my outdoor space looking lush and healthy One pesky problem I’ve dealt with is scale infestations on my autumn sage plants. These small, sap-sucking insects can do quite a bit of damage if left unchecked In this article, I’ll walk through how to identify, treat, and prevent scale on autumn sage.
What Are Scales?
Scales are tiny, oval-shaped insects that feed on plant sap. There are both armored and soft scales but both can weaken and even kill plants when populations explode. These pests attach themselves to stems leaves, and other parts of the plant and insert a needle-like mouthpart to suck out sap.
As they feed, scales excrete honeydew – a sticky, sugary substance. Sooty mold often grows on the honeydew, turning leaves black. Heavy infestations cause yellowing, wilting, stunting, and dieback. Scales also spread diseases like mosaic virus.
Identifying Scales on Autumn Sage
It’s important to check for scales regularly so infestations can be treated right away. Look along stems and the undersides of leaves for bumps that resemble fish scales, armor, or shells. Common scale species on sage include:
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Brown soft scale – Brown, oval bumps up to 6mm long
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Cottony cushion scale – Fluted, white egg sacs
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Gloomy scale – Circular, brown bumps 2-3mm wide
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Oystershell scale – Elongated, translucent bumps with yellow centers
You may also notice sticky honeydew and signs of sooty mold on leaves. Leaf yellowing and branch dieback point to heavy infestations. Inspect new plants thoroughly before bringing them home.
Treating Scales on Autumn Sage Naturally
I prefer to use organic and non-toxic methods when dealing with garden pests. Here are some effective natural treatments for scales on autumn sage:
Use Neem Oil
Neem oil is extracted from the neem tree and contains azadirachtin, which disrupts the hormonal system of soft-bodied insects. It also smothers both soft and armored scales. Mix according to label instructions and thoroughly coat all leaf surfaces at 7-14 day intervals.
Apply Insecticidal Soap
Insecticidal soap kills soft-bodied insects through contact. The soap disrupts cell membranes and causes the insects to dehydrate and die. Coat infested leaves, stems, and branches, targeting the undersides. Reapply every 5-7 days as needed.
Try Horticultural Oil
Horticultural oils smother scale insects by coating and suffocating them. They also deter feeding. Mix according to label directions and completely cover the autumn sage, including leaf undersides and stems. Reapply every 7-10 days for 2-3 weeks.
Spray With Water
For light infestations, simply spraying the plant with a strong jet of water 2-3 times per week can dislodge scales. Focus on undersides of leaves and stems where scales hide and feed. Reduce watering stress before attempting this method.
Wipe Away by Hand
On small plants or very light infestations, rubbing alcohol on a cotton swab or gentle rubbing with a toothbrush can mechanically remove scales. Check regularly and remove any remaining insects. Discard infested trimmings in sealed bags.
Prune Heavily Infested Parts
Prune off any heavily infested parts of the plant. Sterilize pruners between each cut with rubbing alcohol to prevent spreading. Remove and destroy the clippings immediately. New growth should appear within several weeks.
Release Beneficial Insects
Natural predators like lady beetles, lacewings, and parasitic wasps can control scale populations. Attract these beneficials with companion plants like dill, fennel, and cilantro. You can also purchase them from garden centers to release onto affected plants. Monitor results and reintroduce more predators if needed.
Preventing Scales on Sage
Prevention is the best medicine when it comes to garden pests. Here are some tips to reduce the chances of scales on your autumn sage:
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Inspect new plants very closely before purchase
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Check for scales frequently
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Keep plants healthy with proper light, water, and fertilizer
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Prune for airflow and structure
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Use row covers as a physical barrier
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Wash off plants with strong spray every 1-2 weeks
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Avoid excess nitrogen which attracts pests
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Remove and destroy heavily infested parts immediately
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Encourage predatory insects like lacewings and ladybugs
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Rotate plantings to interrupt pest cycles
With diligent monitoring and prompt treatment, scale infestations can be successfully managed. Combining chemical control, mechanical removal, and cultural practices is key to protecting autumn sage plants. Maintaining vigor through proper care also bolsters the plant’s defenses. With a little time and effort, your autumn sage will once again be the envy of the neighborhood.
Scale Damage
Along with allowing fungal diseases to thrive through their honeydew deposits, scale harms your plant by depleting it of sap, which therefore hinders the plant’s ability to send nutrients through its entire body. Scale also causes cellular damage to the plant, making it structurally weaker. If left untreated, the scale will damage and weaken your plants and, most likely, eventually cause them to die.
Before You Begin
Before taking steps to eliminate scale on plants, you must ensure you are dealing with scale and not plant disease. It is often confused for fungal or bacterial infections, like leaf spots or blight.
Pruning Woody Sages
FAQ
How do you permanently get rid of scale on plants?
Does vinegar get rid of scale on plants?
What is the best spray for scale?
What kills white scale on plants?
How do you control scale in a garden?
The most effective tool for controlling scale is prevention. Healthy plants are more resistant to pests and diseases. Keep plants well watered during summer to prevent stress from heat and drought. Plant tree and shrub varieties that are less susceptible to garden pests.
How do I get rid of scale on my houseplants?
If you’re struggling with a bad infestation of scale on your houseplants, you may want to repot your plants in fresh soil or spray a bit of horticultural oil on the soil line to keep scale nymphs from spreading. Was this page helpful?
How do you get rid of dead scale?
STEP 4: Gently wipe off dead scale insects using a soft, damp cloth. Some plant owners may choose to wash off their plant in the sink. If you’re concerned about overwatering your plants as you wash off the dead scale, another effective method is using a damp microfiber cloth.
How do you treat a scale infestation on a houseplant?
When examining and treating your plant, try to do so in a well-lit room so you can better see the extent of the scale infestation. Keep your tools next to you as you go and make sure to wash your hands after removing scale from your houseplants. Scale can leave and come back, so make sure to also clean the area where you keep your plant.