It is often advised to use lemon to get rid of scale in the kettle. But if you don't have a lemon or you want to transfer it to washing, you can take other products, or rather their cuttings.
Details
You can use potato or apple peels for ecological washing. They will help to soften the scale and facilitate its removal from the walls and bottom.
You just have to throw the skins into the kettle. Pour a little water, 150-200 ml, to cover the skins. After the water boils, it should be turned off, but do not pour out the water, but let it stand for three hours.
The scale can be easily removed with a sponge without any extra effort.