Hi Carla, the wand I use and a pic of washing the underside of foliage are the first 3 pics on this album page: Toys
That wand needs to be repaired and I have a shorter one I am using until then. I get soaked using both. I just stay drier longer with the longer one :) I wash the foliage twice a week. It takes about 3 hours to get all our roses done.
I used to wash the underside of foliage about once every 2 weeks. A grower in Hawaii showed me how he did it when I was stationed there in the 70s. In 2004, we had a severe spidermite infestation. I began washing foliage every other day to knock them down. I had quit using fungicide that year. I had tried different ones for a few years. Foliage had been better before used the stuff. I noticed that the powdery mildew magnets we have were clean even though conditions were perfect for pm.
I began cutting back on the washing once the spidermite population was down. PM began to show a little bit when I only washed them once a week.
Blackspot is not a problem here for healthy roses. I have been talking about washing foliage for a few years now. I have been contacted by growers in Europe that have success reducing blackspot by regular washing. They wash early in the day so foliage has a chance to dry. We don't have to time the washing. Humidity is usually so low here that I can have damp foliage at night and it isn't a problem. I'm not trying to get the experts that say water won't help fired up. I'm just reporting what I have been told by people I know are good rose growers.
I have to adjust the schedule some when certain roses are in full bloom. Iceberg is the first that comes to mind. If I get all those blooms full of water, they flop on the ground. A quick wash when they are in bloom works ok. Roses with strong stems get washed as usual when in bloom.
Another note: Some leaves get impaled on thorns. Deb follows me around the yard and frees them. I think she only does it so she can laugh at me getting soaked.
Sorry about getting so longwinded answering you. I kept thinking of other things to mention :)

Most of the time is spent washing the underside of foliage. The tops of leaves get a quick spray as I move around.

Thanks Dave. I'm thinking of this for spidermites also.

Carla

I washed so often to get rid of the spidermites. I had read they hatch every few days. I figured washing every other day would make for a inhospitable environment for them even if they didn't get washed off. I'm a nut and did that for over a month before backing off on the schedule. I imagine there are still some mites out there but they don't hurt the roses that we can see.

We have a friend who does this and the roses, like Dave's, are just stunning. I wanted DH to do that and I even bought the wand and everything, but he let the dog play with the wand and that was the end of that.

Dave--

That fern leaf peony is INSANE!!!

I love it...I never heard of such!

Hi Digger! Hey you left out the part it sure feels good when the temps get over 90's, especially at 110 to have the water on you. I will point it up in the air about every 10 minutes just for cooling myself off:)

How's your weather now? Got some nice foliage emerging yet??

Thanks Patricia, I like hearing if it works (or not) from folks in other areas.

Ronda, Fernleaf Peonies are pretty neat. I'm not a peony fan but I like these a lot. Deb absolutely loves them :) The foliage is unbelievably soft. They love zone 5 and below. Haven't heard of any in zone 6 and 7 that have had good luck with them. Haven't heard of them returning in spring for warmer gardeners.

LOL, you weren't supposed to mention that Leslie :) Folks are supposed to feel sorry for me being a slave to the roses. Deb even enjoys it when the weather is hot. She gets my attention and points up. The mist feels so cool. One reason we moved from the CA central valley was to get away from those 110° days. It rarely gets to 100 here. Average temperature in the hottest months is in the 80s.
Snow flurries forecast this morning. It should get into the 70s for the first time by the weekend. I can't even believe how much green cane and new growth we have. Climbers only have tip damage. We have leaves already on Starina and Magic Carrousel.

Well, Dave, you know my area all too well, and the guy who does this, you would probably recognize the family name from your time spent here, but he is a very meticulous rosegrower and very fastidious in his care of roses and he says this is the answer to washing off disease/insects before they get a toehold.

Is this a special long wand? If so, where can it be purchased? Thanks in advance.

I've been washing off my roses for years but not twice a week. I may try this and see how it works. I do get blackspot and PM usually later in the summer though. Maybe if I start washing more often I can keep that down a bit.

I love those peonies too. I wonder...I always like to push the envelope.

KYRose, it just has a "neck" life shape where it attaches to the hose, just kind of crooked like a squash neck. I think I got ours at Lowe's. Of course, the dog made several pieces of it pretty quickly. We are going to get another one this year because it will help also with cleaning/clearing fountain out.

Patricia, we go through on an aphid/slug patrol before I wash the roses. Slugs are easier to track down before. I spot damage and can usually find them close. I just like to squish aphids :) Your friend's logic works here.

I should mention here that I don't always do all the roses the same day. Sometimes it works out that I have time to wash all at one time. That is usually the weekend. I'll wash a third or half one day and some the next. It seems crazy but I enjoy the chore.

Kentucky rose, I got the long wand (adjustable to almost 5 feet long) at Lowe's. I haven't seen them anywhere for a few years. That is the reason I am rebuilding it. I'm adding a few features to it :) The one I am using now is 3 feet long. Walmart has carried it for several years and Deb likes it better. (not because she gets an employee discount) The 5 footer requires her to use both hands if it is extended to full length. Gotta admit, I can feel the workout in my forearms after using the long wand one-handed for 3 hours. The 3 foot wand is much easier to use unless you have stout forearms and strong hands.

Seil, please let me know how it works if you decide to try it.

Seil, Deb asked me why I didn't suggest something I advised a few others of. They didn't know about investing all the time and effort on washing all their roses. I thought it would be a great idea to only wash a few and let the rest be controls for their experiment. That idea met approval from all I mentioned it to. Most decided to try it on their worst blackspot magnets feeling what did they have to lose :)

This begs the question: Can BS spores be washed off.

Carl

I don't know from personal experience Carla. I have been told by several growers that blackspot is significantly reduced on their roses when they washed regularly before bs showed on foliage. None have claimed water will cure blackspot once it is established. Most feel it slows the spread of the nasty stuff. They have no proof. That is just what they observe.

I was in a hurry and forgot to say that I have read that overhead watering is supposed to spread blackspot spores. That is the reason usually given not to. Those people seem to believe bs spores can be washed off.