You are thinking along the same lines I am. Big, established roses with extensive root systems should not need frequent watering, though they will do better with some. By all means use compost topped with mulch. I like wood chips, free from local tree trimmers. My instincts suggest that we should not over-fertilize. We want the plants to have what they need, but not so much as to encourage more growth than the available water will support. I use alfalfa meal so that the decomposing wood chips don't tie up all the nitrogen in the soil. Remember that this nitrogen will eventually be release back; it is borrowed, not robbed.

Your young roses will probably not survive on monthly watering. I suggest deep weekly watering for the first year or two or three until they develop an extensive root system. Your gray water comment tells me you are already planning to recycle water.

People who have done this suggest that the summer bloom and repeat bloom may be reduced. This would not be surprising to me, since the plants to into survival mode. I'm willing to have this happen so that I can continue to have roses. Companion plants in the once-a-month area should be similarly drought tolerant.

I'm trying to put a positive spin on this, thinking of it as an adventure rather than a blight. Think of all we will learn. In the end, I believe we will get just as much beauty and perhaps even more satisfaction from our gardens.

Rosefolly

We're in the same ballpark.
Some roses are leaving here. Few Austins will remain -- they seem less drought-tolerant.
The Teas and Chinas, once well-established, should handle sparser watering.
I think Noisettes, too.
We have in the past watered 2- to 3-X a week.
We are cutting back to twice, and will step down to once a week.
If we have to cut further, we will do that.
Nothing's getting a lot of pruning or feeding.
If they get raggedy in the hottest part of summer, so be it.
We have been giving the dishwater to the roses for some time now, and warm-up water, also.
If things get really tight, I think a greywater system is going to be a lifesaver.
If we can make use of shower water and laundry water, that's going to be a big help.

Jeri

Oh, I'm hoping I won't have to pull out any Austins - I'm one of those people who has to brace herself every time a plant needs to be pulled out - I think it's one of the reasons I compost! (Gotta put those weeds to use!)Golden Celebration & Graham Thomas just went in last winter, but they're so huge - it seems they must have deep root systems (or will eventually, if they make it). Some of the others aren't as aggressive, tho.

I'm scheming on the various ways I can reduce water use indoors & recycle any water that I do use & put it to use outdoors.

I'm also trying to put a positive spin on this. We need a reminder that water isn't an infinite resource, especially given the population growth in states with summer dry seasons, and the uses to which we put it - gardening, cleaning, ag & manufacturing processes.

However, I do love those roses....

I agree with what's been said. I grow established roses with no summer water and a heavy mulch. Many roses can take this; those that can't eventually disappear. Our being able to do this may depend in part on our soil: most of the garden grows in several feet of pure clay, which is very water retentive; we also get good rainfall in other seasons of the year.

Roses that don't get any water for several weeks will stop flowering. If it continues dry, eventually they'll defoliate, as my 'Safrano' did, an established plant in a hot and relatively stony area. This doesn't necessarily mean that the plant's dying; it's a survival strategy. Next the top growth will die. Roses can come back from the roots. I don't think any of these extreme consequences will happen on your watering schedule, but give a rose a year before giving up on it, especially if it's an established plant. I think that if your roses have been regularly and generously watered you will need to accustom them gradually to a leaner diet. Your plan to do that sounds good.

Melissa

Published by Frances Lincoln, there is a book called Beth Chatto's Gravel Garden. It is not a rose book, but is invaluable for ideas for companion planting in drought situations. Beth Chatto gardens on sand, in a part of the U.K. which gets an average of 20" of rain per year.
Her garden has never been watered.
It is also a very good read, and the beautiful photographs, show the results.

There are some wonderful resources available that might help us rose lovers. A book my husband and I love is Brad Lancaster's "Rainwater Harvesting for Drylands" (2 large paperbacks)and we also learned a lot when we took the permaculture design course in 2006. We're planting our roses in wells (as we do our fruit trees)surrounded by berms or on high-fronted terraces to capture as much water as possible during the rainy season (our permaculture teacher says that "the best place to store water is in the soil.") The wells make it easy to deep water once a week or so in the summer (young roses only). We're also trying to only plant really tough, water-thrifty roses (in our area that's teas, chinas, noisettes and foundies)and have stopped pruning in the winter as that's when our roses really shine (from October through June) so why cut them back as they're enjoying the rain and flowering? We don't try to force bloom during the summer and if we prune for height or space, that's when we do it. I think this regime just might be sustainable for us.

And of course we also save kitchen and laundry water in wheeled buckets and garbage cans and take it out to our precious roses and fruit trees. We have no irrigation (black PVC "snakes") and are very happy we don't.

I love hearing how others are dealing with the water crisis. We'll need to pool our creative ideas if we're going to be able to continue growing our beautiful roses...

Thanks for your input, everyone!

I have one local example of roses being grown without any watering. An employee of a local engineering firm planted 2-3 dozen in their parking lot. A couple of the varieties are Madame Alfred & Sombrieul & perhaps Mermaid. They primarily bloom in spring, but as they aren't pruned, they're quite large. I love seeing these roses - they intermingle wonderfully & they're such a surprise.
Actually, the ones grown on the west side of a 10' or so fence bloom into the summer - I imagine their roots are quite shaded. We also have heavy clay soil, so any rainfall lasts longer than it would in loam.

Oops, I described incorrectly the orientation of the roses in the unwatered parking lot. The roses that bloom into summer are on the east side of the fence. That certainly makes more sense! I think some even bloom into autumn, before the rains descend on us for the winter.

On the brighter side, I noticed one distinct advantage of our climate - several roses have a few buds: Madame Alfred, White Maman Cochet, Abraham Darby, Sweet Harmony, Fortuniana (hundreds), & a few other roses. Bring 'em on!