Those look to be 'Iceberg' roses, the best and easiest roses for Southern California, which might shock you since you seem to be having trouble with them.

Most plants that flower need to have the old flowers removed. You don't need to remove all the flowers individually, you can take off the whole cluster when most of the flowers are finished.

The bugs you are talking about are probably aphids. Stop spraying them with insecticide. It only makes things worse. Spray off the aphids as much as possible with a strong blast of water from the hose. In time, predators will take care of all the aphids if you don't use insecticide. Insecticide kills the beneficial bugs just as fast as the bad ones.

The white stuff on the foliage is powdery mildew (PM). It's been a late and rainy spring and PM is rampant this year. Make sure your roses are getting enough water, because thirsty roses are more vulnerable to powdery mildew. As summer comes on the PM will go away. You could shorten the roses a little by cutting them back and that will remove a lot of the PM.

It looks like someone has trimmed the roses into a hedge like shape. They are in a very narrow bed. Think about widening the bed in the future. It will look a lot better and you will have less lawn to mow that way.

Congrats on the new house!

I'd like to add that it looks like you've got Thrips too, one of the buds that isn't open all the way has the brown markings on it. I had a terrible time with them this year and went the organic route with no success. However I bought a bottle of bayer( b-cy something or other was the active ingredient) now my white roses are pristine and gorgeous! Daedhead the rose clusters to the first leaflet with five leaves, once they are brown and dead they aren't attractive and need to be removed. Powdery mildew spreads on dry foliage, I'd recommend giving them frequent showers first thing in the morning(so the leaves dry quickly and they don't stay wet long enough to develop blackspot) make sure to wash the tops and bottoms of the leaves. Happy gardening!

I didn't know that Iceberg require dead-heading. I've always thought this rose can self-clean itself (i.e drop its petals freely onto the ground).

Has anyone tried milk in water to treat the mildew problem?

Actually, in SoCal, you don't generally see a lot of mildew on Iceberg foliage. This spring, though -- WOW -- all bets are off, so to speak. Moreover, if your house was a foreclosure, I bet those roses may have gone without much water, for months.

Hose-washing really will help with that problem. It solves a multitude of problems.

Those browned blooms likely opened in really dank weather, and you won't have that much trouble when things warm-up/dry-out. But as HoovB notes, cutting off the old rotted blooms will get rid of the un-sightly mess, and should encourage the formation of new, better-looking blooms.

Iceberg's almost a cliche in Southern California, but that's because it's so tough, and so lovely, with minimal care.

Jeri

I'm not familiar with that climate, at all, but if folks are suggesting water spray, I can tell you that that's how I deadhead my frequent bloomers. I don't have time to do a true deadheading on all my roses, so I zap them hard with the water spray!

The cluster bloomers like you show is where that really saves time. Keep in mind, the rose may still use some energy on what that leaves --the hip still possibly trying to form-- but I love hips, too, so I'm not bothered by it, myself.