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Are your houseplants beleaguered by scale bugs? It's a common problem but never fear – you can make short work of these pests and have your plants looking beautiful again.
In this blog post, we'll discuss the simple steps needed to quickly kill scale on your houseplants and keep them away for good. From the right insecticidal treatment to the importance of proper humidity levels, everything you need to know is right here.
So let's get started on the path towards pest-free plants!
- Overview of scale insects
- Armoured or soft scales
- The life cycle of a scale insect
- Common signs of a scale insect infestation
- Steps to Combat Scale Insects
- Step 1: Identify the infestation.
- Step 2: Prepare the plant.
- Step 3: Wipe down the plants' leaves.
- Step 4: Apply the pesticide or treatment.
- Step 5. Monitor progress.
- Natural Methods for Controlling Scale Infestations
- Chemical Pesticides for Treating Scale Infestations
Overview of scale insects
British gardens are home to an incredible range of scale (scientific name: Coccoidea) insects – with over 25 diverse species found in Britain, from the tiny 1-6mm Pulvinaria and Diaspis all the way up to Wisteria scales measuring 10mm in length.
Adult scale insects are usually covered in waxy shell-like cover. There are more than 25 species of scale insect found in British Gardens. Each species has a different host range and life cycle. They feed by sucking sap and some can weaken host plants, many excrete a sticky substance (honeydew), which allows the growth of sooty moulds.RHS
These spots can look like white, brown, yellow, or black bumps against the green foliage – and, if left unchecked, will continue to grow as more scales feed on the plant's juices.
Armoured or soft scales
Scale insects come in a range of shapes and sizes, but generally speaking, there are two categories: armoured scales and soft scales.
While both can get into your garden and wreak havoc on your plants, they have very different defences.
Armoured scales literally armour themselves with a hard shell and an external layer of wax, making them stronger against predators.
In contrast, soft (bodied) scales rely more upon their adaptations to deter predators – most notably their sticky honeydew secretion, which helps them stay put even when their environment is disturbed.
The life cycle of a scale insect
Scale insects are fascinating creatures that have a unique life cycle. They begin their life as an egg, which hatches into the first larval stage known as the crawler.
These tiny critters, each no bigger than the head of a pin and equipped with six little legs, can scamper from plant to plant in search of their next meal.
The crawler then attaches itself to its host plant and feeds on its sap using modified mouthparts (proboscis). It then moults several times until it reaches the adult stage, where it reproduces.
After that, the female lays eggs to start the life cycle anew. It is unusual to see male Scale insects as they cannot feed and die a few days after maturing.
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Common signs of a scale insect infestation
If your plants are displaying a blend of yellowing, stunted growth and small bumps or a white waxy coating on the leaves, chances are you have an infestation of scale insects.
The bugs themselves can also be seen clinging to the plant stems and underside of leaves, often accompanied by a sticky honeydew secretion that can attract ants.
In severe cases, webs or sooty mould (https://www.rhs.org.uk/biodiversity/sooty-moulds) may also be associated with the infestation. If any of these signs are spotted on your houseplants, it is time to immediately combat the infestation.
Steps to Combat Scale Insects
Fighting scale insect infestations in your home can seem daunting, but with the right guidance and approach, it doesn't have to be.
Step 1: Identify the infestation.
Keeping an eye on your plants is the best way to stay one step ahead of potential pests!
I like taking a few moments each week to give my plants some TLC by carefully cleaning off the dust on their leaves and making sure any critters don't try and sneak in.
If something suspicious pops up, there's no need to panic – isolate that plant as soon as possible so you can keep your plants' neighbours safe!
Step 2: Prepare the plant.
Once you've noticed you have a scale problem; it's time to take action!
Start by removing any leaves that are infected and then go in for the bigger stuff – like cutting away parts of your plant that have been badly affected and are too damaged to be salvaged.
Step 3: Wipe down the plants' leaves.
If you only have a few scale insects on the leaves, then you can dab a bit of isopropyl or rubbing alcohol onto the bugs, which will kill the pests.
If you have a bigger infestation, then you will need to wipe the leaves down with a damp microfibre cloth.
Some stubborn bugs may need to be scraped off with your fingernail .
Step 4: Apply the pesticide or treatment.
Treat them with special sprays or insecticides to tackle this issue and ensure no more pests enter your future indoor garden oasis.
Sprays that either kill or protect against scale insects:
- Bug Clear 2
- Neudorff Bug Free Bug and Larvae Killer
- Vitax organic plant guard spray
- Plantsmith Bug Control Spray
Spray your selected pesticide onto afflicted areas of the plant and clean any nearby surfaces which may have come into contact with the spray.
If you decide to go the biological route, this is the time to add them to your infected plant.
Be sure to follow the instructions carefully and stick to a regular schedule for the best results.
Step 5. Monitor progress.
Check your plants regularly following the treatment to make sure they are responding positively to the treatment, and take further action if necessary.
Battling a stubborn infestation may require multiple treatments, so keeping your patience is key!
Natural Methods for Controlling Scale Infestations
Natural methods, such as regular hosing down the plants' leaves in the bath with a shower stream and, as mentioned, hand-picking scale insects, can be used to remove or reduce existing infestations.
Physical methods for killing scale infestations are important in pest control. Not only can they be used to reduce the populations of these pests, but they can also help keep them from spreading to other plants.
For example, rubbing a finger along a branch where the scale is hanging out can help remove individual insects.
Pruning infected branches or twigs is another effective way to stop the spread and reduce population size.
In addition, when plants become heavily infested, spraying with a strong stream of water may be necessary – enough pressure will knock the scales off without damaging the plant.
Additionally, natural deterrents such as sticky traps are good ways to safely and naturally reduce pest populations if you have an infestation.
Fortunately, there's an eco-friendly solution to keeping your houseplants healthy – biological controls that are just as effective without harsh chemicals!
These solutions range from the simple, like introducing ladybugs (but not always the easiest indoors!), all the way up to complex predator nematodes such as Steinernema feltiae that specifically target scale insects.
While these solutions don't always work overnight, they offer lasting protection from scale infestations.
Whatever you choose, rest assured knowing these methods of control will give lasting protection against
Horticultural oils are derived from petroleum or vegetable sources.
If they can't breathe, they will die from asphyxiation when the carbon dioxide and other toxins reach dangerous levels.
According to a study by the American Society of Horticultural Science, horticultural oil provided more effective control against armoured scales than insecticidal soap; however, the latter gave greater protection against soft-scale species.
Insecticidal soaps are a non-toxic way of keeping pests away from your home and garden.
To effectively deal with pesky insect invasions, I recommend utilising special soaps containing active ingredients like neem oil.
Basically, these special soaps work by dissolving the outer layer of the insect's body, leading to dehydration and, eventually, death.
They are also effective at controlling pests in both the larval and adult stages, meaning you get more bang for your buck!
Neem oil is derived from the Azadirachta indica tree and has been a widely used remedy in India for centuries.
It's a great natural insecticide that can be used to fight off all kinds of insects, such as aphids, mites, whiteflies, beetles, and caterpillars.
Neem oil prevents insects from obtaining the essential hormones they need to mature; without these hormones, their development is stunted, and they won't be able to mate or reproduce.
And what's even better? Neem oil also repels future bugs from invading your garden! So you can count on it to keep pesky insects away with its unique combination of repellency and insecticidal properties.
Check out my blog post to learn more about making your own DIY spray at home using neem oil!
Chemical Pesticides for Treating Scale Infestations
Chemical pesticides are a common method used for treating infestations of scale insects.
If you're dealing with scale insect infestations, potent ingredients like pyrethrin, permethrin, and bifenthrin can be sprayed on the foliage to help eliminate them.
However, these chemicals can also harm other beneficial organisms in your garden, so they should be applied sparingly.
Also, note that multiple treatments may be necessary to bring the infestation under control, depending on its severity.
How is climate change impacting the frequency and severity of plant scale insect infestations?
With climate change comes a whole new set of challenges regarding houseplant scale insect infestations.
Warmer and drier air and changing weather patterns can create an ideal environment for insects to proliferate and invade homes.
If these infestations become more severe, they can threaten the health of your houseplants and even introduce toxins to them, making it essential to take preventative measures to protect your home and plants from being invaded by these pests.
Does vinegar kill scale?
Vinegar is a fantastic natural cleaner that has a wide range of uses.
While vinegar can certainly kill scale insects, alcohol rubbing spray is the preferred method for killing them.
If you decide to try vinegar to get rid of scale on your houseplants, be careful when using it, as vinegar is acidic, so you want to make sure you take the right precautions.
Can a plant recover from scale infestation?
Scale infestation on plants can certainly be a daunting issue to deal with. Still, if you take the correct measures, it is possible for a plant to recover.
It is vital to act quickly in order to keep the infestation from spreading further, which will make recovery much easier.
Can scale live in soil?
If you are wondering if scale bugs can live in the soil, the answer is yes!
Female scale insects lay their eggs into the nooks and crannies of plant material, eventually leading to larvae that hatch in soil.
The larvae will then feed on roots and other organic matter from decaying plants or fallen fruits.
This can lead to a localised population of scale insects if left unchecked!
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With a few simple steps, you can quickly eliminate scale from your houseplants and keep them looking their best.
Start by making sure any new plants are free of scale, and don't introduce them to your home. If you already have a plant with scale, start with insecticidal soap or rubbing alcohol. Then make sure to clean the leaves regularly with a wet cloth.
To prevent future outbreaks, increase air circulation around your plants and give them plenty of humidity. With these steps in place, you'll be well on your way to keeping your houseplants healthy!