Orange growth on underside of Hollyhocks leaves (nasty!)

I have two plants that came up from last year. They both are about 4 ft. and getting ready to bud. They are in the ground, with potted plants surrounding them.
I have been fighting aphids(Black? the ones on my hibiscus and roses were green) on my Rose of Sharon with Dawn solution and blasting with the hose. It has worked so far on the aphids? but I think all that water twice a day on the hollyhock was not a good thing.

It is like a orange mold or mildew growing on the underside of the bottom leaves. I striped off all the leaves that it was growing on, and they went out in todays trash so I can't get a picture. This stuff is nasty. Is there anything else I can do to help get rid of this? Will it spread?

I have grown hollyhock in that location for several years from last years seeds. I usually just have to remember to stake them. This is the first sign of problems.
bev

That's called rust and it's a pain in the butt to get rid of. I'll do a little research and see if I can find what's best to treat it with.

Unfortunately some hollyhocks are prone to it and will get rust almost no matter what you do. Hopefully plantfreak will have some ideas of what you can do, but the usual advice I've seen is to buy varieties that are resistant to rust because it's hard to treat.

I have always sprayed with a solution of baking soda and water, it takes a bit of time but it works. if you begin the spraying regimen before the rust starts it does prevent it.

Does it work once the rust is already there? Many of these sorts of problems if you spray some appropriate product before they start then you can prevent them, but once they're already there it is much harder to get rid of.

It doesn't completely eradicate, it helps, but removal of the infected leaves helps more.

If it helps I'll try it. I will mix up a batch and spray it on the good leaves today before it rains.
What is the mixture you use? and how many times do you spray it? I will spray the ground too. That seems to be where it started, the leaves were worse there. It can't hurt the plants at this point. There is a lot of new growth without the spots.

Sorry for the short answer before; I got interupted in mid-thought. Ecrane's right, you can only treat rust preventatively. Our nursery usually suggests any solution containing chlorothalonil (like Daconil by Ortho). I agree with the others suggestions of removing the infected leaves including ones that have fallen off. (Put them in a plastic bag and throw them away). Then spray the heck out of any leaves, stems and buds you have left about once per week. Next year you'll know it's coming and you can keep a closer eye on them.