How to identify scale on plants
The sap-sucking insect looks like a shell; they mainly attach themselves to the leaves and stems where all the goodness is, but can be found anywhere on the plant.
Kevin Parker is a senior horticulturist at The Greenery Garden and Home. He says, “There's what they call a hard scale and then there's a soft scale. The hard scale cover themselves with a really hard, almost like turtle shell coating that protects them from predators.”
As the scale saps the suck out of the plant, it secretes something called honey dew, causing black sooty mould to grow on the plant. So if you notice either the sap, or the sooty mould, it could be scale.
How to get rid of scale naturally
The best way to get rid of scale is with oil, says Kevin.
“You can use white oil or what they call horticultural oil. Or you can use the botanical type of oil - there's one called eco-oil, which is more natural, or you can use neem oil.”
Although as Kevin points out, neem oil is quite expensive and comes in a small bottle, so if you’ve got a large scale problem, you are going to need a lot of bottles.
For the oil to work, it actually needs to come in contact with the insect, so make sure you are spraying both the top and bottom of the leaves and down the branches and main stems.
Additionally, Kevin says to avoid spraying oil on your plants on hot sunny days as it will burn the leaves. Also avoid spraying if it’s going to rain, as the oil will wash off.
If you have a really bad infestation, Kevin says you may need to do a number of treatments.
How to permanently get rid of scale insects
Another problem with scale is that it’s hard to tell if it’s actually dead.
“Because it’s like a shell that's attached itself to the plant, even after you kill it, the scale doesn't pull off,” says Kevin.
“So it can look like you've still got scale.
“The only way to really know is to grab one and squeeze it. And if nothing comes out, then you know that the insect is dead - or if the sooty mould goes away.
How to prevent scale in indoor plants
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