About insecticidal soap:

Unless folks don't bathe, I feel confident that anyone reading this is familiar with soap from a very young age. However, there are NUMEROUS incarnations of soap thanks to our modern chemical engineers, but only a correctly formulated one will kill insect pests.

I've been using insecticidal soap for about a decade and IT has NEVER killed even one of my roses - NOT EVEN my tiny newly received bands. The first thing that happens when I take roses out of the delivery box is I thoroughly spray them with insecticidal soap.

Of the choices for insecticides, it is the most environmentally friendly. PLUS, one of a beginning gardener's first objectives is to understand N-P-K, the abbreviation for the components in commercial fertilizers. The K stands for potassium. The insecticidal soap I use is formulated with potassium. As it biodegrades, tiny amounts of potassium become available to the roses. And who doesn't love a product with more than one use?

In the link below, see the Wiki article on potassium deficiency.

I also recommend the Wiki article you will find if you search N P K.

Here is a link that might be useful: Potassium Deficiency