22,153 Garden Web Discussions | Roses
If only my Memorial Day could look like yours, Susan. Mine always has thrips damage and simply can't take our heat. Maybe things will get better in a year or two. It didn't help to transplant her this spring either. Anyway, your photo is gorgeous and that look of pink porcelain was one of the reasons I bought MD in the first place. Thanks for posting your photo. Diane
When I lived in that area, many roses defoliated during the worst heat of July & August. I kept up the watering, fed them at the beginning of Sept. & enjoyed a new flush of leaves & blooms when the weather moderated. Usually, in September, the nights start to get cooler & give the plants some relief.
Fall blooms were often the best of the year in that climate. And once the roses recovered they were beautiful into December.
Defoliation is the plant shutting down because of stressful adverse conditions. Sometimes it's only one stress that causes it, but more usually it is a combination.
So for example, a rose being stressed by a lack of water will not need much pressure from black spot to start shutting down. Similarly, a rose stressed by an untreated black spot infection will not need much pressure from a lack of water to start shutting down.
Unfortunately, if the shut down continues for too long it can be fatal. Roses and other plants are not immortal, and they do die if conditions are adverse enough.
I have a hedge of 6 Gold Medals and I love 'em. They were planted earlier this year in May and they have grown about a foot taller and have produced blooms non-stop.
The only cons are chili thrips love 'em and the blooms fade to a brownish white, sometimes with a tinge of green.
Thank you everyone for the responses!
My Maria Stern gave me a ton of variants of itself. Sometimes bi-colored, sometimes pink, sometimes orange. I never knew what I would get when I woke up!
When I picked up Gold Medal it had a few buds on it I let it keep. The first one bloomed yesterday, and it was gorgeous! THankfully it Faded little when I picked it today. And I LOVE how it looks next to Intrigue and Red Sensation. Not quite sure who has the better scent between GM and Intrigue though.
These are all in pots on my patio,
That would be my first concern, windeaux. Andrew, there is a very convenient thread about breeding for disease resistance on the RHA, posted by David Zlesak this morning. You might find it interesting. Kim
Here is a link that might be useful: Vance's disease resistance rose breeding review
be kind! I think there are a lot of reasons why people may have boring lawns, and don't take joy in "flowers and bugs and dirt and sweat"
--they may be dirt-and-bug phobic. I am.
--different priorities for their time and money. boring and neat is far better than neglect.
--climate. Traditional lawns and flower beds in my area of the country are a no-go.
My neighbor is very neglectful as a gardener. Nothing ever watered, all browned and dying, nothing ever weeded. And to top things off when her hubby and her put in a raised bed box with landscape timbers they built it up against their front deck only three sided with the back next to the LATTICE, so all their soil keeps eroding away and they just keep dumping in more crap topsoil as a filler. Drives me nuts! I have to bite my tongue! lol
MulchMama, the full paper is not yet available to me through the university. The wording in a reviewed accepted scientific paper is subject to scrutiny by the reviewers and the editor. This wording is also consistent with what I have read in the scientific literature.
The commercial fungicide that they compared with is Topaz (a penconazole based "azole" family fungicide).
For plants I assume that the greatest concern is whether the Topaz is damaging the mycorrhizal fungi relationship with the plant roots.
"Abstract
In order to quantify the importance of ectomycorrhizal fungi on nutrient uptake from the coarse-soil fraction of a haplic Cambisol (alumic), a microcosm study that allowed for nutrient budgets was designed. Ectomycorrhizal- and fungicide-treated spruce seedlings were grown on isolated and cleaned gneiss fragments (6.3 mm > à> 2 mm) from 90 cm soil depth. The substrate was the only source of Ca, K and Mg. Ectomycorrhizal seedlings showed no signs of nutrient deficiencies and biomass increased significantly compared to initial seedling biomass. Ectomycorrhizal seedlings seemed well adapted to survive on the coarse-soil substrate and acquired Ca, K and Mg from the coarse-soil substrate. Gneiss fragments of the ectomycorrhizal treatment were covered by fine roots and ectomycorrhizal hyphae, as observed microscopically. Fungicide-treated seedlingsâ root development was retarded, and shoot biomass only increased from stored nutrient reserves of the seedlings. The suppression of EcM colonization by the fungicide Topasî apparently caused a root growth inhibiting effect. Furthermore, the extinction of mycorrhiza initiated an increased nitrification and acidification and a consequent nutrient cation release triggered by nitrate in the drainage."
A Google Scholar search with the keywords: penconazole and mycorrhizal fungi
Here is a link that might be useful: link for above
With 'Charlotte Armstrong', 'Peace', and their immediate descendants, there was a big step forward in vigor and perhaps in mildew resistance for hybrid teas, but I'm skeptical as to how much improvement occurred in the forty years after that. Over that period the overwhelming majority of new roses were HT and Fl that were fully susceptible to blackspot, and breeding consisted mainly of crossing two successful cultivars of that type. Apart from exhibition form, how were the top roses of the 80s clearly superior to the roses of the 50s like 'Tiffany' and 'Queen Elizabeth'? Is there a super-fragrant red HT better as a garden rose than 'Chrysler Imperial'?
It seems to me that American commercial rose breeding during that period was stagnant except for the pursuit of novelty colors and needle-nosed exhibition HTs. California breeders ignored the rest of America's need for more winter hardiness and blackspot resistance. The groundwork for real improvement was being laid in Iowa, Wisconsin, and Canada, but the truly superior roses never made it to the garden center until Conard Pyle made a deal with Bill Radler around 1990.
This post was edited by michaelg on Tue, Jul 30, 13 at 14:38
Again, depending upon your criteria (in this case, disease resistance and cold hardiness) the answer to the question is going to be "it depends". But, basing it upon the criteria of foliage quality, foliage density, bush habit, vigor, flower production, actual resistance to midew and rust in THIS climate, there have been dramatic improvements in bush, foliage and flower quality. I wish I had my old slides of the decade beds at The Huntington Library I took thirty years ago. It was a living museum by decade (as was the Descanso Rose History Walk, prior to the more recent "renovation" of the rose garden) where you could observe and study the improvements by decade. Viewed that way, the changes have been dramatic. Kim
Michael, thank you for the crash course,
I must say , as a gardener, I have had a very steep learning curve this past 2 weeks.
Soo glad to hear this is not lethal to the plant, I did break a few of the canes when sinking them, I did not take any further precaution than to snip them off and make a clean cut.
Do you have any suggestions on a what I should have in my rose arsenal?
I'm not too fond of heavy chemicals but am resigned to having to step it up to keep the roses healthy.
Thank you, K
Insecticides are rarely if ever needed. Scout for chewing insects and remove them. Bring your pest control questions here.
Fungus diseases very with the climate. When you bring questions here, you should name your state in your sig line or in the post.
In the east, and to a lesser extent in the midwest, blackspot fungus can defoliate most rose varieties repeatedly during the season. This can cause less hardy varieties to die over winter if subzero conditions occur. Some varieties are resistant (ask here) while others are hardy enough to survive without fungicide anyway, though the foliage may not look so good.
Living in an area with extreme disease pressure, I use Bayer Disease Control for Roses. . . (containing only tebuconazole) about every two weeks, to control blackspot and other fungi. It is available at some Lowe's and online. If you want to avoid synthetic fungicides, copper soap (Soap Shield) is probably the most effective option. Sulfur sprays may be adequate if you apply often enough.
Do not buy combo pesticide products (3-in-1 etc.).
That doesn't look like a rust problem to me. Looks like you have bugs chomping on your leaves and your buds. I found this web site that shows photos of common problems with roses, what it is and what causes it.
Here is a link that might be useful: pets and diseases on roses
Michael, a lot of these roses seem to have several names - Millie has also been Ghita and Mum in a Million, Claire has also been Liliana, Eleanor has been something else which I cannot recall, Philippa seems to have vanished off the radar but is probably just using a different name........so Clara may well be known by another name altogether.
I have my own name for them - Irritating Eyesore.
I have Sandra, a beautiful lavender. Love the color. Sorry about the fuzzy pic. She is upright,and stiff in her growth pattern