Question
QUESTION: Please help me!This is urgent!I am from Malta, a little island in the middle of the Meditterenean.I have a Dracaena Marginatas at home.My mum, gave it to me as a present.This plant was situated in her garden which has an orange and lemon tree(citrus). Lately i have noticed black spots on the leaves!and the leaves are turning yellow!So i started a thorough search in the Internet and i have discovered that the plant has a disease called Florida Red Scale!I can confirm this is i have seen photos on the internet.I keep this wonderful plant inside my home and under a window!Could you kindly help me and tell me how can i get rid of this FRS? Is it dangerous for us humans? Even the oranges on the tress have it! please help me! I thank you!!

ANSWER: Vanessa,

FRS is an insect, not a disease and it is not dangerous to humans. Under that hard scale is an insect and the scale is its armor. To kill the insect you have to get through the armor. You can use rubbing alcohol with a q-tip or if there is way too many on too large a plant you can put the alcohol in a spray bottle and spray the entire plant twice a week for a month. That will catch any scale that hatches out of eggs before it matures to form that hard shell.

There is also a systemic insecticide called Bayer Advanced Tree and Shrub Protect and Feed that you can use. It is a systemic product that you mix with water and water the tree with it. The tree absorbs the chemical and it kills the scale. It says you only have to apply it once a year but I find I need to use it twice a year on my bonsai trees. Here in the US it is about $20.00 for a large bottle but you only us 2 tablespoons per 5 gallons of water so a bottle will last a long time.  I do not represent the company but the product does work when it comes to getting rid of scale. You might want to check to find out if it is safe for eating the oranges if you use it. A nursery in your area may have something to get rid or scale  on the orange trees that would keep them safe to eat. This would work when they are in bloom but there are no oranges. Rubbing alcohol is safe for the oranges and leaves them still safe to eat.

Good luck.

Darlene

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QUESTION: thanks a lot for your quick and very useful reply! I already rated your answer .. full marks! I just would like to ask one last question! When you advised me to rub alcohol on the leaves .... what alcohol were you referring to? please excuse my inexperience on plant care! But i am very eager to learn as i love plants! Thanks again!

Answer
Vanessa,

70% Isopropyl alcohol known here as rubbing alcohol, usually sold in a drug store or pharmacy or Walmart for under $1.00 a pint. It is used for cleaning medical instuments, sometimes wounds but it burns a lot. It will kill any insects on contact. Sorry I didn't explain better.

Darlene