22,153 Garden Web Discussions | Roses


Maybe Sunset Celebration (Warm Wishes) doesn't like extreme heat--could somebody comment? Mine is not a tremendous bloomer, but it grows well enough and the flowers are very attractive and have good fragrance. Mine was pushing 7' tall until I just now took a couple of feet off with deadheads.
The spots on SC foliage in the picture appear to be cercospora fungus disease. I have a lot of that this rainy summer.

One thing you should understand is that rose blackspot is chronic in all eastern and midwestern gardens. You can't get rid of it by pruning. You have to deal with it in one of the three ways Jim suggests. I use the Bayer Disease Control spray concentrate.

IF this is blackspot (and I still think better images would ensure a correct diagnosis) you have decisions to make.
1. To spray (may/may not correct the problem)
2. To live with the problem
3. To re-plant with roses resistant to that fungus.
If you decide to spray, take time to check out the chemicals you will be using, and be sure you want to add them to your environment.
For every one of the available garden chemicals, there are active ingredients, and these offer greater/lesser degrees of danger. The chemical in Bayer Disease Control is tebuconazole. Information on it follows:
"Tebuconazole is a triazole fungicide used agriculturally to treat plant pathogenic fungi.
Though the U.S. Food and Drug Administration considers this fungicide to be safe for humans, it may still pose a risk. It is listed as a possible carcinogen in the United States Environmental Protection Agency Office of Pesticide Programs carcinogen list with a rating of C (possible carcinogen). Its acute toxicity is moderate.[2] According to the World Health Organization toxicity classification, it is listed as III, which means slightly hazardous."
"Due to the potential for endocrine-disrupting effects, tebuconazole was assessed by the Swedish Chemicals Agency [3] as being potentially removed from the market by EU regulation 1107/2009.[4]"
It is not allowed for sale in New York State.
==============
If you are going to spray with any garden chemical, DO use a mask and protective clothing. If you can smell the chemical, you are breathing it. If you spill it on your skin, wash it off immediately, and thoroughly.
Jeri

The sun issue is cause we haven't had any....its done nothing but rain. And overcast. And rain....they were all terribly wilted yesterday but we got an inch of rain...sigh....lol. it's supposed to be 90 today and overcast....will keep my fingers crossed.


My feelings are you need to experiment to see what works best for you in your location...
Like here I'm finding out our soil doesn't need very
much fertilizer so I'm mainly back to top dressing with cow manure OR horse manure OR compost once every growing season or every other.
Along with using wood chip mulch...
Sometimes I add alittle alfalfa meal into the mix...
This seems to keep the earthworms happy and they
continue to loosen the soil and secrete there poop
which keeps the soil & roses happy...
So I say experiment and just be careful not to burn the roots and leaves of your roses by overfertilizing...

I usually fertilize about once a month. And I do so right up to frost. Some people will tell you to stop at least 6 weeks before your first frost but I like my roses to go into winter well fed.
Did he say what type of fertilizer he was using? Is he using that Miracle Grow hose end sprayer? That's my bet.

Henry,
The cutting off of a suspect cane only works if you catch the problem when it's on a single cane. I think a friend in Asheville may have done this for a Knock Out bush in his neighbor's KO bed this past fall. As of this spring, the bush remained healthy. (This is one of the members of Asheville Blue Ridge Rose Society who have been trying the two strikes and you're out for quite a while now at my urging.)
Something that had bothered me for the past two years was the spread of RRD within beds of KO. Some beds stayed healthy; others were almost infected randomly, but wind dispersal ISN'T random. Then I saw a yard crew working (blowing) near one of the beds I've been following and (not using a blower at home for anything) I surged into this century and thought about what damage those breezes could do.

I don't really impulse buy roses... I ponder them long and hard. I impulse buy all the other stuff that goes in the beds with them. I bought a small white dianthus and a double white lisianthus to go in my White Bed. I just got an heirloom (or a recreation of an heirloom) white carnation with that old time peppery scent to it - got 2 of them, a ruffly white one called White Rabbit, and and ride and white thing that looks surprisingly like my Rock & Roll rose! Both are supposed to become 3x3 foot plants with lots of the old peppery scent that I adore. I got scabiosa at a local nursery months ago. Then I got some plant supports online from Gardeners Supply to help hold them up because they're ALL falling over - into the driveway where they will get demolished, so they have to stand up and be safe!
Heh. The list of my impulse buys in the garden is LONG. It's just not the roses themselves.
Melinda

Honestly, all my roses have been impulse buys. I've bought..6, and only 2 of the 6 were planned. My Blue Girl was my first rose and what I planned on. Maria Stern I grabbed after a customer came through my line at Lowe's and I fell in love with her color and smell. N-Joy I grabbed after seeing her how neglected and unwanted she looked(fried buds and little leaves). Intrigue and Red Sensation(Which was supposed to be a double grafted with All American Beauty) I grabbed after seeing a new shipment come in. And Last but not least Gold Medal was my only other planned buy after MS died :(
Oh yeah, I found a miniature rose discounted at HD haha.
I'm not good about planning, you should see how crowded my patio is now hehe! But I'll blame working at Lowe's if ya'll don't mind xD


I don't have Crimson Glory, but here in Livermore I site the dark reds so that they are in shade from about 2 - 3 p.m. on and, fortunately, I have such spots. That includes Francis Dubreuil (Barcelona), Oklahoma, Mirandy, Purple Buttons, etc. Above 100 degrees, they are going to fry anyway, but this strategy at least gets them through the low to mid 90s in decent condition.

I certainly wish these website folks were as diligent as they are where I work. The site crashes or otherwise 'acts up' too often.
I have just replaced my dead mouse. Thank you all for your input.
I will have to think of another rose for that location.
I wonder if any of the miniatures can take the heat or sun a little better.
andrea


Thanks for the encouragement hoovb I know that your yard is beautiful. Wish I could have as many beautiful roses as you do. When I lived in Vista CA is was never a struggle w/the roses but here it is pretty bad. Dry, hot then freezing in the winter w/ eating bugs the size of a fifty cent piece. But I will prevail!


Were you able to rule out herbicide damage from lawn care products or weed killers?
If it is not caused by herbicide damage, then it is imperative that you carefully dispose of the roses in sealed tight bags. Make sure you get the roots also. If you don't, you endanger your other roses--and your neighbors' roses.
Terrible having to face up to it, isn't it. Happens to most of us, sooner or later, if that is any consolation.
Kate