I love Clivias, but recently yellow and black worms destroyed all my plants. Which insect killers can I use and how frequently must I use them?
Various types of worms can affect garden plants. Those that cannot be picked off can be treated with products containing Bacillus thuringiensis (Bt), a natural bacteria that kill worms without harming plants. Neem oil may be helpful as well. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/prevent-caterpillars.htm