21,402 Garden Web Discussions | Roses


As mentioned above the same antivirus defense: "RNA silencing functions as an antiviral mechanism in plants, insects and mammals..."
This 2013 published scientific paper: " Cooler Temperatures Destabilize RNA Interference and Increase Susceptibility of Disease Vector Mosquitoes to Viral Infection"
From author's summary: " Specifically, we demonstrate that RNAi, a critical antiviral immune pathway in mosquito vectors of human disease, is impaired in insects reared at cooler temperatures."
H.Kuska comment. This 2013 paper is additional evidence that Nature has chosen the same immune system antiviral pathway (with the same tmperature dependence) that is postulated in roses, and found in other plants, insects, and mammals.
Here is a link that might be useful: Cooler Temperatures Destabilize RNA Interference and Increase Susceptibility of Disease Vector Mosquitoes to Viral Infection

Kippy - I think I'll give Neptune another chance, used to have it. I think there are some great recommendations here and I am so grateful. There are a couple of Austins I've wondered about I don't think were mentioned here, Abraham Darby and Pat Austin. Does anyone have either of these?

Agree with 'kentucky_rose' as a preliminary diagnosis based on photo (I'd much rather be doing it in person)
Curling of the leaf edges is one of the early signs of powdery mildew infection.
What variety is this? Some varieties are more resistant than others.
Are you using a fungicide? Which one? Also some information on your cultural practices like watering and mulching would be helpful
If you are already using a fungicide labeled for PM, it may be that you have encountered a resistant strain of the fungus. PMs are notorious for developing strains that are resistant to certain fungicides.
I know I raised more issues for you than I settled, but I'd be hesitant to go further without knowing these.

I wonder if that's why my bands are doing so well. I never heard of this approach before, but my potting mix was equal parts peat moss, dehydrated cow manure ("Bovung" at Home Depot), and shredded hardwood mulch, all mixed together in a wheelbarrow. I layered Jobe's Organic Knockout Rose Food into the pots as I filled them, and this fertilizer contains active "bacteria, mycorrhizal fungi plus a unique species of Archaea" which I'm guessing helped activate the composting process. And everything got a soaking with diluted fish/seaweed emulsion. The mulch must be working much like the buried "woody debris" and the manure, rose food and fish/seaweed emulsion must be working like the high-nitrogen "green material" added to compensate for all the high-carbon "brown material" of the mulch. I'll have to look into this "hugelkultur" more....
:-)
~Christopher

Jeri:
A good water spray - best with a water wand so you don't get soaked yourself - is the preferred control for aphids even for a small infestation. It's important to cover the top and bottom surfaces on the plant, hence the water wand.
The water spray will knock the aphids off the plant but still make live prey available as a meal for their predators, so the predator population can continue to build without having your roses subject to damage.
Not only do insecticides reduce the predator population directly, but they leave no live prey, so the prey-predator cycle has to start all over again.

And here comes a big negative on waiting. I'm pulling out a hedge of about 30 KOs a section at a time and replacing them with hollies. I KNEW BETTER than to create a monoculture like that, but i inherited more than half of them with the house, polka-dotted around the yard. I added to them to finish out the hedge when i lined up the ones we transplanted. Here's what i know for certain:
1. KOs are the most susceptible roses, but they do infect close neighbors.
2. If you think it's infected, it almost certainly IS. Several that i pulled out just to be cautious had unmistakable horrid growth concealed at the bottom.
3. Since the bigboxes are still selling KOs by the truckload, your neighbors will be stunned and horrified when they stop to ask you why


No. Dependence on that list may do harm.
"Instantaneously recognizable" can't depend on those symptoms because roses react differently to RRv and symptoms change with time and exposure to (having the disesase in, and presumed titre increase) the disease.
The stems and leaves are not always bright red, nor do they stay red/purple in all cultivars if they start out red.
Growth may be extremely fast.
Excessive thorns are not present on all infected cultivars, nor are they present on all stems.
And on and on. It's a darned shame that the state extension people don't go to gardens in their own states and report what is IN their states.
At one time, the extension people all reported that RRD wasn't a problem for cultivated roses.
Then there was a comment unsupported by any published, juried paper, that RRD was also in the fruit trees. That, too, dropped after a year or two.

Thank you Ann. It is probably hard for those not in science to realize that in a sense scientists often are like blind men trying to describle an elephant from where they are standing. This is why I was glad to see the two meetings this spring of the "experts" to compare notes.

Also wanted to add, I just looked up what zone I live in. It's 6 (I think?! I live in north eastern Oklahoma.) I need to look for plants that fit this zone number, right? I had no idea there was so much more to taking care of a rose bush than just planting it and watering it. Diseases, Dr. Huey, and zone preferences, it's a whole new world to me!

Welcome to the forum, tbaron. I'm about 30 miles north of you, in southeast Kansas. You might want to go back and edit your registration to include your zone. Note my "z6 KS" right after my user name. Or at least always include your zone in the first sentence or so of your post.
By the way--good gardening zone. That means you can grow almost any rose, especially since, with climate change, zone 6 is transitioning in places into zone 7. I think mine might actually be zone 7, or very close to it, by now. The zone number means that the rose should be cold hardy to zone 6 or higher numbered zone.
Try to get all the roots out if you dig up Dr. Huey--or he will return--kinda of like Dracula always returns in the next movie! (Actually, Dr. Huey is rather attractive--if he just didn't have those other irritating habits!). Dig a hole about two feet wide and a foot deep--I'd think you'd find most of the roots that way. Perhaps in the center, directly under the rose, you might have to dig deeper if it has had time to established a strong centralized stabilizing root.
And have a bag of humus/compost (from Home Depot or Wal-Mart or such place) ready and dump 1/3 or more of it in the hole and loose soil leftover. That way you will be all ready to plant a new rose when it arrives since you will have already amended the soil. At that point, all you will need to do is dig a hole, plant, and water! : )
You might want to browse some rose pictures over on the Rose Gallery--get some ideas of alternate choices. Plenty of pics posted often on this forum also. And see also the Antique Roses Forum, especially if you like the David Austin shrubs (like Munstead Wood). And feel free to ask about any roses you find appealing.
Happy rosing!
Kate


I grew roses in central Fl. (Winter Haven 1980-1998) and S.E. Fl. (Hollywood 1973-1980 and Port St Lucie 1998-2008). I learned the hard way that you needed foliage on you're roses while you were trying to get flowers. Every time I lost my foliage from black spot or spider mites while I was feeding them, I ended up with small blooms while they were trying to put new foliage back on the bush's. A lot of times even a month or so after the folige was back. If you have a bush that spends several months during it's growing season just fighting to keep foliage on it, you aren't going to get good blooms. I exhibited my roses (all class') so I needed big blooms. A healthy, happy bush will produce good size blooms, sometimes even during the hot humid summer. A top notch exhibitor in Lakeland told me something a long time ago. Stems produce foliage. Foliage keeps the bush healthy during the natural hot, humid summers. Think about this. You buy a water oak about 8' tall with a lot of foliage and new growth. Plant it and let it get settled in for a couple of months (May/June). Go out and strip all the foliage off of it and then throw down a bunch of fertilizer. If it doesn't die, it will put on little, deformed foliage and the tree will probably be stunted for a long time. Just think about what happens to your rose bush every time it looses foliage while it is actively growing and trying to flower. During the first two yrs after I bought a rose, I just took the flower off until the bush was 7'/8'. Then only brought it down to neck high. I also stopped feeding the first part of Nov. and watered the bush's real good Nov., Dec., Jan., & Feb. Usually having good size blooms during this time. The middle of Feb. I would prune the bush's down to waist high and stripped off all the foliage. If I had any basil breaks or new strong lower canes when I pruned, I left them alone. I would start feeding again the first of March and would generally have good big blooms for two bloom cycles before the summer heat kicked in real good. You still have mostly young bush's that are trying to do everything at once. Keep them healthy and happy and give them time to grow up :)

Yes, for Heaven's sake, quit chopping them back.
You are creating stressed plants.
Allow them to grow to the stature they're genetically-predetermined to reach. Then, they can quit putting energy into a doomed attempt to grow, and put it into blooms.
Jeri





That's more than enough sun for good bloom.
In my Pacific Northwest climate zone, despite days of peek-a-boo sunshine (even during the middle of "summer"), variations in temperature, rain (we like to call it "a light drizzle of raindrops"), my KO roses thrive. No BS, no disease...they are hardy! :) I have a KO rose planted in my front yard along with spring through fall-flowering bulbs. I am adding a few more KO roses to the front yard.
I have my (arthritic) hands full tending to our small landscaped rose garden in our backyard. I love my OGRs and other non-KO roses. This is my little haven, a place of peace and undulated promise of hope.
KO roses are not particularly liked by one and all. I respect others' opinions regarding the same. I am foraying in a path that seems to work for my life.
Enjoy your KO roses!