The 'Seasonal Stream' on the south edge of our property is supposed to run in the months of December through March. By 'run' we mean that in places it's eighteen inches wide and not so much as an inch deep and in other places it's completely below the surface of the ground. Whenever we get more than two inches of rain in an hour, though, it runs twenty feet wide, and three feed deep and roars like a freight train. The drought starts in February, but a snow storm or two will feed the seasonal stream with moisture well into spring.

By April it is dry a foot down, and it is expected to stay just about that dry until the next winter. Of course, because it is at the bottom of a big rock-lined basin and because precipitation from a quarter mile away drains through this 'stream' there is some lingering subterranean moisture here for a week or more after we get more than about half an inch of rain. My cunning plan was to take advantage of all these facts and plant roses in this stream bed. I figured that in the winter the roses wouldn't mind being in running water up to their knees. And during the summer they would enjoy some subterranean refreshment.

My trial run was a measured success. Four roses planted in spring of 2011 survived through winter and all last year. So this year I committed to planting the stream with roses. I made a small 'Old Rose' bed featuring Marie Louise, Compte de Chambord, Nuits de Young, Madame Plantier Duke of Edinburgh and Gros Choux de Hollande. And next to it I planted Graham Thomas (whom I like to believe would be honored to share a bed with some favorite old roses), Liebeszauber, Gingersnap, Mardi Gras, Oranges and Lemons, and Cary Grant. Then, realizing that these roses would be young this year, and therefore small, I planted between the roses a mess of dahlias.

I would declare the experiment a success. The golden dahlias in the modern rose bed are glorious right now. I'd never have planted dahlias there were I not trying to start a rose bed. Many of the roses are thriving too, though in some cases they are a little hard to see thanks to the dahlias.

But of course nature frequently does something different from what we expect. And this is where the interesting part starts... soon. This year we had maybe six inches of rain in July. Then we had some rain almost daily through August. The frequency of precipitation reduced to two or three times per week in the first two weeks of September. The last week or so has been pretty dry. That is, not a lot of clouds and not a lot of rain. The relative humidity, which was pegged at about 70% for two months has dropped below 45% during all daylight hours. But of course that level depends on where you measure it. Inches above a running stream it is higher.

In any case, the seasonal stream started running in early July and it's been running ever since. Some of the dahlias - the ones in the lower 'old rose' bed found their feet to be too wet and expired quickly. I feared for the roses. Every day I go out and look at the old roses in that bed and I expect them to have collapsed into a heap of mush; but they look bright, crisp, green, and happy. They have grown vigorously, although perhaps not quite so fast in running water as when the soil is simply moist. I know that the advice is not to plant roses in standing water, but perhaps freshly fallen running rainwater is richer oxygen and carbon dioxide than your typical standing summer pond. Not certain what accounts for my unexpected success here.

The stream has had a slightly different effect on some of the modern roses. Yesterday I noticed that Cardinal Hume which had been growing like gangbusters before the rains had lost about half its leaves to blackspot and was preparing to lose another quarter. Next to it, Gingersnap still had a lot of healthy foliage, bit it had a few leaves completely blackened by the fungus. Liebeszauber has some yellowing leaves, but the cause appears not to be blackspot, so I'm little worried. Perhaps it is smothering from lack of oxygen, the canary in the coal mine, so to speak. Speaking of canary, all three Sunsprite planted in this area are happy as a clam. Far away from the stream I have spotted just a few yellowing, black-spot infected leaves on Winsome, Toscana Vigorosa, and Paradise Found. These appear to be the aged leaves that roses tend to drop just because they are old. But they are lightly spotted with black spot: cause for raised alertness.

It's been an even better chance to discover which roses are immune to powdery mildew. The infestation began with Permanent Wave in an area where some dahlias were troubled by the disease last monsoon season. Many nearby roses were untouched: City of Leeds, Hobby, Kimono, Geisha, Ginger, Sexy Rexy, Crocus Rose, The King's Rubies, China Doll and Chevy Chase. Zepherine Drouhin got hit next, but recovered with some copper soap treatment. It has some deformed leaves, but new growth now seems to stay well-formed. Madame Alfred Carriere got the next wave. The fungus infested only new growth. Interestingly, Mme Alfred's leaves got distorted but they never got very powdery from the mildew. It was as if the rose was successfully fighting off the infection though being affected by it. Or perhaps my copper soap ministrations helped it, too. Baronne Prevost had a touch of the same thing, but is fairing well.

The very tippy tips of Ilse Krohn Superior were affected to the point of turning white with powder. That's the only place in the garden where I have observed the infection to get so advanced. Interestingly, established leaves seemed to shrug it off completely. Climbing Pinnoccho and Shocking Blue had slight leaf deformity, but no visible powder. Nearby Berolina, Rise 'n' Shine, Moonstone, Charles de Gaulle, Gemini, Rock and Roll, Blush Noisette, Emily Gray, JACclam, Looping, Grande Dame, Paradise Found, Rainbow Sorbet and Cherry Parfait, were unaffected. It looks like there might be some infection spreading to Double Delight. Handel, Antike 89, Penny Lane, and Desiree Parmentier are unaffected. I had thought Europeana was unaffected, but I am wondering whether its aged flowers are getting it. South Africa has remained free of infection as have Winter Sunset and Golden Celebration, but Folklore and Duftzauber 84 seem to have been lightly affected. The glossy leafed multiflora climber Psyche was free of it in all places where it lived in the sun; but where it both touched Lavender Lassie and spent much time in the shade, it was hit hard. Darlow's enigma and Ghislaine de Feligonde were unaffected. Only one sprig of new growth on Hermosa was affected, but it was devastated. That may have been the new wave of aphids, though.

I observe that shiny foliage seems to correlate pretty well with resistance. And that points of infection with powdery mildew are in all cases soft, new growth. I was interested to see that the first and only rose to show signs of both blackspot and powdery mildew was Merveille de Lyon. The new leaves at the top were deformed by mildew. The old leaves at the bottom are yellowed by blackspot. The middle-aged leaves in the middle are still relatively healthy, but the plant looks a wreck. Remind me not to plant Baronne Adolfe de Rothschild until I've learned how to control both infections.

My second round of spraying has been a biological control agent labelled "Biocide" that I bought a few years back from Gardens Alive. I'm hoping that the bacterium responsible for controlling the fungus is still viable. Spraying it seems to have materially exacerbated my fall allergies in a way that did not seem to happen with copper soap. Because the powdery mildew infection sort of advances in waves that correlate with weather, and because the effect of infestation seems a little subtle for some days while the fungus establishes on a leaf, it's a little difficult to tell whether success is aided by intervention or whether any success I might have is just a fortunate artifact of drier weather. Today it looked like plants that had been affected are no worse off than they were yesterday or the day before. That's good, because when the disease is winning, it can colonize a lot of new territory fast. And really susceptible new growth can become covered in powder in a day or two, it seems.

This is my first serious encounter with powdery mildew. At this point the only plant that I can say is 'ravaged' by the disease is Permanent Wave. I am contemplating waving goodbye permanently. The others that have been affected have been touched by it but have not really lost any leaves to it. This is also my first encounter with black spot on this property. Now I understand the limits of my good fortune with respect to raising roses here. If the weather becomes so damp that I do not need to water my roses, I will need to spray them. I wish I had understood that when I gardened in NJ. There the rule would have been the other way around: "If it is dry enough that I don't have to be spraying for blackspot, I need to be watering my roses."

The seasonal stream is still running in places. The air is getting drier and cooler every day. In four weeks frost will kill most of the rose leaves in my garden and the fungal infections along with any predatory bacteria will fall to the earth for winter. Horticultural oil and more biocide will arrive soon and be applied next spring. We shall see then how the rose beds in and not so far away from the seasonal stream will be affected by this year's particular events. Stay Tuned.

Steve I find your carefully chronicled detailed observations very interesting and possibly useful in my garden as well. I don't have a seasonal stream but I do have a ditch that drains the driveway. I have planted mainly Earthkind roses in or right next to it and found that they did very well - except a couple that get some sort of leaf disease that seems rather worse than blackspot. Sea Foam is the worst. The leaves seem to burn up sudddenly. She spends most summers nearly nude. Last summer when it was extra hot and dry, blackspot was not a problem. I have never had mildew, that I know of anyway. I find that the old roses fight off disease better than the hybrid teas - even the disease resistant ones only live a few years for me, then gradually fade away cane by cane. I will be anxious to hear how your experiment continues.

Thanks, Porkpal. I do hope that some good might come of it.

Writing that piece did convince me to move Permanent Wave far from existing roses where it will get more direct sunlight. Perhaps Merveille de Lyon will make good company for it, soon. If these measures (and more typical weather next year) do not cause the problem to abate, I guess I really will need to purge the garden of a few roses.

One can never have too many roses. Ever. Or shoes.
That's the law.
I took notes on your notes, and hopefully next year I'll be able to really look at my plantings in the same way, and make some better landscaping choices.
Even though our climates vary widely, on roses we share, I agree with your assessment 100%.
Porkpal, friends convinced me to buy multiples of Sea Foam and plant a whole hillside in them, and I am sorely disappointed, I've seen it growing well for others, but it doesn't do squat here. The K-State extension experimental station here tests for Earthkind, and they have a dozen of them that grow beautifully. Mine spread, but they don't bloom. What good is that? I didn't feed mine, but they didn't feed theirs either.

Cindi - With your Sea Foam, threaten them with a bottle of RoundUp. If they don't bloom, they get rounded up! But I've noticed a lot depends on soil, too. My roses in my front yard do a lot better than in the back yard. The front yard's soil is getting very nice now due to all the mulch that's been rotting on it for a few years whereas the back yard, well, it's still incredibly crappy. And the front yard gets less sun than the back yard.

Wellllllll I may not need that roundup. we'll see. My lawnmower broke right before I went to California, and I had not mowed for at least 2 weeks because it had been so hot and dry. Of course it rained and cooled off while I was gone. My husband got home, fixed the mower, and it looks like he mowed that hilllside. The weedy grasses that popped up in there hid the roses, so I can't blame him.
Maybe a severe pruning will encourage the Sea Foams to bloom? It's so late in the year, I kind of doubt it.
Steve, how do you handle weeds growing at the edge of the seasonal stream? Our pond is really low right now, as it usually is this time of year, and we have weeds 4' tall. I can't mow them because the ground is too soft. Once the rains come, they'll be under 2 feet of water, but for the 3 months or so that we're fairly dry, it's ugly. Do you have to walk the banks with a gas trimmer? Or spray chemicals? Or do you plant roses thickly enough that they keep the weeds down? Here, at least, roses don't grow dense enough to serve that purpose.
So far, i don't have cattails or loosestrife, but I am looking out for them in amongst the ragweed, knotweed, and pickerel.

My seasonal stream has enough sand deposited that I can just walk near it or in it without sinking in at all. I know this sounds crazy: but so far, I have just been pulling weeds out by hand. It means, of course, that they have to get about 18 inches high before they count. As for grasses I got desperate this spring when four Sunsprite and one Mardi Gras were being threatened with about the same fate as your Sea Foams. They had spent all of last year buried deeply in native grass and I lost two or three roses in the thick of it. So I used Ornamec - available from Wildseed Farms. There are one or two spots where I've left native grasses in place - clump forming ones that make head-high seed stalks simply because mulch would wash away.

There's a stretch that is unplanted. It's mostly grass beneath junipers. This I mow with a string trimmer maybe twice per season. I think my garden is on a much smaller scale than yours. And I have not been aggressive about managing the edges. I'll plant a bed, get it under some moderate level of control, then plant another. Outside those bounds things are totally au natural, which means they blend perfectly with all the rest of the properties around us.

Assuming they had gotten established, I'd bet those Sea Foams will be back. And they'll probably bloom better than ever.

I have trouble with weeds and grass growing up through my roses and Sea Foam is more plagued than most because it is low-growing and thorny which makes it difficult to weed - however for a good part of the summer those weeds offer the only green foliage that Sea Foam has.

Ouch! Maybe Sea Foam is not a good rose for hot climates. I understand from experience that it's among the least fun rose beds to weed because of its vicious thorns and its habit. I wonder if weekly weed-whacking and annual Ornamec treatment when combined with a few inches of mulch might bring things under control. But who has time for all this work?

I finally hired a twenty-something person to weed and mulch for about four hours per week. Progress feels a little slow, but the person has worked in a nursery and is good at distinguishing weeds from flowering plants. Started in August and we're about 80% of the way done. One more bed out of five to go. Might be done this week or next. I'm more interested in steady improvement year over year than in perfection; and that helps a lot. I've been pleased to find that watering and feeding my roses seems to have made weeds just a little more manageable. I like to believe they are being out-competed by my roses and perennials. Or maybe my constant hovering over the garden this year has kept me pulling up the worst offenders through the season. In any case, this year the garden is looking much better than last year.

I hope that it's not just random noise; I'm going to be planting a few more beds next year and I need to be able to concentrate much of my effort on getting the new plants settled in.

Not sure this helps, but when I was reading Beth Chatto's book about growing plants with low water requirements I was struck by one of her practices. She did not mulch the first year, but instead got a great army of volunteers to weed every week or two. The idea, I think, was to let as many weed seeds germinate in the first year as possible, then dig them out of the garden. In the second year when the weed seed population was lower and her new plants had grown a bit, she put down mulch. Her ultimate goal was to create a perennial garden that required essentially no weeding or watering.

I thought that disturbing the soil in any way, including pulling weeds from it, increased the chances of more dormant weed seeds being brought up to the surface.
That's the philosophy behind the chemical control, no-till methods our county extensions recommend. Compost, poison, then mulch.
I had an area that didn't get mulched and the plants in that area seemed to do fine in the heat this summer. I wonder if the lack of mulch caused the plants to send roots deeper? The ones I keep on the dry side on the summer do better in winter stress.

It does bring more dormant weed seeds up to the surface, Cindi. You're right, but if you continue to weed without letting the new weeds go to seed, you'll have fewer weeds each time, and eventually none.

Sometimes the process takes some time and persistence.

There's an old joke about an American who is visiting one of the great old English castles with their great gardens and perfect lawns stretching out to the horizon. He comments to his English host.
"Your lawn is so vast, and so perfect. How did you ever do this?"
And his host answers, "Weekly mowing and regular weeding. For about five hundred years."

CindiKS said:One can never have too many roses. Ever. Or shoes.
That's the law.

I agree whole heartedly with the never having too many roses part. I only have a couple pairs of shoes, but I think it's a guy thing.

CindiKS said:Porkpal, friends convinced me to buy multiples of Sea Foam and plant a whole hillside in them, and I am sorely disappointed, I've seen it growing well for others, but it doesn't do squat here. The K-State extension experimental station here tests for Earthkind, and they have a dozen of them that grow beautifully. Mine spread, but they don't bloom. What good is that? I didn't feed mine, but they didn't feed theirs either.

My own experience with Sea Foam in NJ was that it did well by the end of its third year; but a lot of things affect rose performance. I've been reading a lot about roses online recently. I've learned that it's just not unprecedented for roses to take five or six years to really settle in. It depends on the rose, of course. Sunset Celebration is evidently one that can wait for five or more years before it starts showing what it can do. And I've heard the same about Teasing Georgia.

One of the things I realized while doing that same work is that some of the wichurana and kordesii hybrids (Sea Foam, Heidelberg, Handel, Grand Hotel ... for example) may do a little better when they are not brutalized by high temperatures, drought, and hot sun - a combination that many tea roses seem to endure happily enough. It's not something I found written down anywhere. It's something I observed from looking at the origin of photos of roses at HMF. Lots of photos. (And assuming that people tend to post photos of roses that do well for them.) It changed the way I think of roses just a bit.

I realized that there are roses that are ideally suited for the cool summer/cool winter marine climates i.e. Northern Europe (many wichurana and rugosa hybrids among them). There are roses that are ideal for cool continental climates i.e. US Northeast (many multiflora hybrids among them). There is much overlap between these groups, but the cool continental roses need more sun and must possess more resistance to blackspot. There are roses that are ideal for mediterranean climates i.e. California and parts of AZ and TX (many of the popular hybrid tea roses among them). There are roses ideally suited to warm continental climates - i.e. Gulf States (tea and china roses among them).

Pretty much all roses will grow in the mediterranean climate, but it seems that there are a number of roses that do not get as large or are less vigorous there. My understanding is that Generous Gardener is a good plant for a wall or an arch in England. Here in zone 7 of Arizona it certainly reaches head height. In California it is said to stop at about three feet, if I remember correctly. Something like this is true of Toscana Vigorosa, though not on quite the same scale. I knew that weather affected the rate of growth of a rose, with the optimum temperature being attained during spring and fall through much of the continental US.

But I only recently realized that it's only roses with a strong affiliation to the tea and china roses that actually do their best in hot weather. Suddenly Kansas and Colorado both seem like more difficult places to grow roses because of the monumental temperature swings, the low rainfall, and the occasional high humidity.

I wonder whether a little PM shade might help Sea Foam until it's been there for a while? Maybe deeper piles of mulch? Or aluminized blankets pinned to the soil with landscape staples to keep the soil cool in summer? Maybe that's a bit over the top? Which direction does the hill face?