Daniel Hanna wrote in
home.com.au:

In nk.net Snooze
wrote:
We've got some whiteflies as well here in San Jose. They seem to like
the tomato and zucchini plants, far more then they like the roses.

I agree - they can really hit a tomato bush but I've never seen these
things take to roses.

I have a few whiteflies around my Madame Hardy; for some reason they only
like her. I spray them with a hose and that seems to dissuade them from
making themselves permanently at home.

It's an odd season for bugs. This morning I found a tomato hornworm
lolling drunkenly on a fuschia branch. It was a large worm too, about
four inches long. I had no idea they liked fuschias, nor did I see any
evidence of how it got there (it wasn't there for long; I persuaded it to
take a little walk with me to the trash dumpster). I'm hoping it doesn't
have friends who like roses.

That depends on the spray. A systemic one will enter the plant and
poison the sap, making the insects drink their own death. You CAN use
those sprays on food crops although I'd personally rather not do that.
On roses, systemic is the way to go.

A neighbor moved and insisted that I take a bottle of some dry
fertilizer/systemic combo. I'm not into feeding with dry fertilizers and
haven't ever used systemics; this one had a primary ingredient of
disulfoton.

From googling through rgr the relevant wisdom seems to be that disulfoton
has a noxious scent and that the concoction, if used as directed, can't
have much of an effect systemically because not enough of it can be used
in combo with fertilizer and it won't protect new growth. I'm disinclined
to use liquid sprays other than milder things like insecticidal soap, but
the thought occurred to me: is there perhaps a granular systemic that can
be used alone, without fertilizer, reasonably effectively, or is the
liquid route the only solution, so to speak?

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