Is it true that scales can't be killed and they say just throw away the houseplant? Then I read about cooking oil dish soap and alcohol all together will kill the scales. Please help. This is the neatest houseplant I have. It's called 'Emina' fern.
Certified GKH Gardening Expert
Scale can be dealt with no problem. You can use these ingredients together to try to get rid of them (though the alcohol may hurt the plant, so it is best to leave it out). Here is the proper mix: https://www.gardeningknowhow.com/problems/pests/how-to-make-white-oil-for-an-insecticide.htm
You may also want to consider neem oil. It is very effective against scale and is harmless to people and pets. You can learn more here: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm