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Well, the verdict is in on Moses' roses regarding black spot.

Moses, Pittsburgh, W. PA., zone 5/6, USA
last year
last modified: last year

I promised I would give a report on my roses regarding their black spot resistance, so here goes.

Remember, this year, 2022, I did not foliar spray any fungicide, nor apply any fungicide granules to the soil for a systemic approach for fungus control...nothing at all.

I cannot imagine a rose garden more beset by black spot than mine. The black spot pressure in my garden here in Pittsburgh, zone 6b, is intense every year.

I'm on a campaign of replacing all my black spot prone roses with new roses, those that I have enough confidence in through researching them as thoroughly as I can that they will live up to their accolades.

The winners are these roses. They are equal in being virtually black spot free with either no blackspot what so ever or less than 10% defoliation. No vigor loss was observed all season long.

Bliss Parfuma, Wedding Bells, South Africa, Pinkerbelle, Apricot Candy, Sweet Drift, Double Pink Knock Out, and White Knock Out.

These are keepers, but had about 10% defoliation. The defoliation did not effect their performance.

Poseidon, Apricot Drift, Popcorn Drift, Moonlight Romantica, and Quick Silver.

These experienced 50% defoliation, which greatly affected their performance.

Princess Charlene of Monaco, Dee-Lish, Quietness, Lady Ashe, and Easy Spirit, They are, however, very free bloomers if sprayed.

The completely defoliating bunch of worthless roses are: At Last, Italian Ice, and the Austin, Scepter'd Isle.

My future plan of action is to remove the complete defoliaters. Return to spraying a fungicide mixed into my Imidacloprid insecticide spray routine. I am planning to renew spraying next year, 2023, since my 12 month soil drench of Imidacloprid which I applied this past spring was a complete failure in controlling the dreaded midge fly. My rose garden is 98% midged right now. Just Apricot Candy and the Drifts, are producing any appreciable blooms.

The 50% defoliaters are being considered for removal, even my Quietnesses.

Moses

Comments (27)

  • BenT (NorCal 9B Sunset 14)
    last year

    Moses,

    Always great to hear from you, although I’m sorry to hear that midge is still such a problem despite the imidacloprid drench. But I agree, might as well mix in some fungicide if you have to spray that imidacloprid anyway!


    I don’t grow Pinkerbelle but I’m always impressed by her and some of the other newer Weeks roses at the nursery. It’s their dense foliage, almost like they pack twice the number of leaves in the same space. All that additional foliage translates into some tremendous flower producing ability.

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked BenT (NorCal 9B Sunset 14)
  • User
    last year

    Rose Midge went away completely about 3 years after I stopped applying Azole type fungicides.

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked User
  • Artist-FKA-Novice Zone 7B GA
    last year
    last modified: last year

    Thank you for the update, Moses, any BS-resistant list is very helpful!

    I can commiserate about having a high BS pressure yard. Even the most touted ones become noticeably defoliated for me by the end of the season.

    This year, Plum Perfect performed the best in this regard. Then again., Easy Does did very well for a few years too until this year, it didn't anymore.

    Being in a pot it probably needs the soil changed and a vigorous pruning.

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked Artist-FKA-Novice Zone 7B GA
  • Kristine LeGault 8a pnw
    last year

    Moses, getting rid of Quietness? Say it isnt so

    How many of us have her because of you ?

    Im glad that Bliss is a good one for you. It is a really a workhorse on my garden.

    Thanks for sharing your findings.

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked Kristine LeGault 8a pnw
  • librarian_gardner_8b_pnw
    last year

    We're all benefiting from hearing about your garden. Thank you for sharing. It's great to hear that Bliss did so well. too bad about your 50% ers. There are some great roses on that list.

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked librarian_gardner_8b_pnw
  • rosecanadian
    last year

    Moses - that is terrible to have such blackspot and midge issues. Good for you for getting rid of the worst offenders.


    Paul - do you have an idea why your midge went away once you stopped spraying?

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked rosecanadian
  • rifis (zone 6b-7a NJ)
    last year

    !!!

    All Quiet (here) on the Eastern Front.

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked rifis (zone 6b-7a NJ)
  • User
    last year

    @rosecanadian Unfortunately, no. I can only speculate. It may have been a coincidence, but I seriously doubt it. Azole fungicides cause endocrine disruptions fish and mammals, so maybe there are other disruptions in the environment we don't yet understand?

  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    Kristine,

    My Quietnesses are now 14 years old. Their crowns are 10" across! Maybe their age had something to do with their bad black spotting. Also, this could have been a once in a generation black spot explosion of intensity. Then too, my 6" growing tip only spraying technique of spraying for midge, which all the roses got in the past, before this year's soil drench fiasco, included a fungicide mixed in with the insecticide. I sprayed all the foliage of roses which had black spot issues, growing tips to lowest leaves. Perhaps my Quietnesses were kept black spot clean by their entire bush sprayed neighbors not spreading BS to them?

    Right now I will give the Quietness bushes a reprieve to see how they respond to my planned resumption of spraying for midge and fungus.



  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    Artist,

    Thanks for your endorsement of Plum Perfect. My preliminary research on it is encouraging. Antique Rose Emporium has it so perhaps a trial in my garden is in order.

    It's a beauty going by the photos seen at Help Me Find Roses.

    Moses

  • KJ (9B, San Jose CA)
    last year

    Moss, so sad to hear you plan to remove Quietness. I got mine because of you and it's one of my favorites. Love it so much.


    Let me add Bliss, Wedding Bell, and South Africa to my list. All good spots in my garden have been taken. Now only the place under North facing fence is left. I am looking for something very disease resistant to survive fall and winter. Also have to be very sun tolerant since that place is baked during summer.

    Moses, Pittsburgh, W. PA., zone 5/6, USA thanked KJ (9B, San Jose CA)
  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    KJ,

    Bliss, Quick Silver, and Pinkerbelle are the most vigorous of the black spot clean roses. Their vigor is awesome. Apricot Candy comes in just a shiver behind the above three, then Wedding Bells, South Africa, and Poseidon (in that order), come in just a tad less vigorous, but still strong and robust. Only thing is, Poseidon needs to prove itself to me a bit more....the bloom seems to come short in durability.

    Moses

  • Artist-FKA-Novice Zone 7B GA
    last year

    @Moses, Pittsburgh, W. PA., zone 5/6, USA


    Here it is now.

    It grew very tall in a large container, I think it's almost 6 ft now ... but then again, I realized I wasn't pruning right to give it that bush form and keep it shorter.

    I am ready with the newly acquired knowledge for next season. That and avoiding the borers :)


    The color is really beautiful, a deep true mauve ...and it looks like it is quite BS resistant too. I only wish the blooms were larger especially relative to the thick, monster canes it tends to develop.





  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    Art,

    Kordes roses, which Plum Perfect is, are known for making monster canes with blooms at the very tips only, when they are young. Once some age is gained, they settle down as yours should do given time.

    Moses

  • Artist-FKA-Novice Zone 7B GA
    last year

    Thank you for clarifying, Moses, and for giving me maximum hopes for Plum who has done very nicely this season, especially in terms of fighting BS. I hope smarter pruning will help in addition to maturity.


    I did not know about the technique of cutting the outer canes shorter than the inner ones to get that bushy look. That probably contributed to Plum's awkward look during its first and second season. It sent one enormous tall cane on one side and all other canes except a thin and short one are on the same side, making it look asymmetrical and leaning.


    Hopefully next year it will behave. No matter what, the bloom color is irresistible.

  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    Monster Derelict Cane?=The Exuberance of Youth

    How to prune a bush to well tailored proportions? It's somewhat like a grade school group photo of a large class...the shorties are in the front and tall kinds are in the back.

    If you have a lot of equally strong canes growing in all directions after pruning all dead and weak canes to the crown, along with deciding what to do about crossed growth, limit the bush to no more than 5 canes. One will be left pointing straight up, the other 4 will point north, south, east, and west. Ideally choose those that grow out at 45° angles. Knowing the above bush rarely occurs, we do the best we can with what we have, balancing left to right and front to back.

    Keeping a badly located thicker, more robust cane is preferred over keeping an ideally placed but sickly, thin cane.

    Moses

  • dianela7analabama
    last year

    Thank you for reporting how all these roses did in your yard. I am always doing research on this topic and waiting to hear of any roses grown successfully no spray on the east coast or any other area with high blackspot pressure. I will be adding them to my list to try. Sweet drift is also one of my top performers here. I also have plans to try the white knockouts.

  • Artist-FKA-Novice Zone 7B GA
    last year

    @dianela7analabama


    I follow you with great interest - you are one of my references - as I am rather close by (North Atlanta).


    I love my Coral Drifts, best performers in the yard by far. When they say "color" and "coverage" they mean it; but I sometimes wonder if I should have gone with the Sweet Drifts instead. They look so romantic and are probably more elegant than the flashy corals but I wanted that splash of landscape strong color along the driveway - something visible from the street as our house is set off further back from the street compared to all others in the neighborhood.



  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    dianela7bnorthal,

    Although your zone 7b is warmer, our black spot pressure is probably the same.

    Yes, please try White Knock Out, which formerly went by the name White Out. As time progressed after its intro a number of years back, it soon proved to basically have the same black spot immunity as the others in the Knock Out series, hence the addition of "Knock," to its name.

    What a self tailoring bush it is, needing almost no keeping in bounds, but keeps a classic, rounded/mounded bush form with just about no effort on our part. Dead heading will go a long way to keeping it pumping out blooms. The individual blooms are stunningly pristine to me, and if it was bred by Austin, it would be a legendary 'sophisticat,' and not just a humble Knock Out.

    Moses

  • Artist-FKA-Novice Zone 7B GA
    last year

    @Moses, Pittsburgh, W. PA., zone 5/6, USA


    Do you like White Knock Out better than the Double pink? I just planted the latter this summer at the mailbox but I thought about the white one.

  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    White Knock Out and Double Pink Knock Out are the best Knock Outs as I see it. All the others have one or more undesirable traits.


    Double Red Knock Out comes next behind the above two because red roses are not my favorite color. I see no other difference between the two, Double Red KO and Double Pink KO, only a bloom color difference. Everything else is equal...two equally great roses with identical traits, just different colored flowers.

    Moses

  • Moses, Pittsburgh, W. PA., zone 5/6, USA
    Original Author
    last year
    last modified: last year

    Artist,

    Sweet Drift can get very wide. Under ideal conditions, age, and with minimal pruning, it can get 5-6' across. It likely does surface root as it goes where limbs touch the soil for an extended period of time. Its growth habit for me is 12" to 16" tall and quite wide, as just stated above, but I keep mine at 3' across. It doesn't exactly sprawl, but its stems grow about 30° from the horizontal, not 45° or more, which would be a better trait, but no real complaint here, just an observation. It would be a great cascader if planted behind the top of a retaining wall.

    The blooms are petal packed, and at the exhibition stage they are lovely. As a bloom matures further and unfurls more, the petals start to quill, which I wish it didn't do since I don't care much for blooms that quill, but otherwise, Sweet Drift is a great rose.

    BTW, SD's foliage is shiny, pristine, and tough as nails, laughing off black spot.

    Moses

  • rifis (zone 6b-7a NJ)
    last year

    “I am planning to renew spraying next year, 2023, since my 12 month soil drench of Imidacloprid which I applied this past spring was a complete failure in controlling the dreaded midge fly.”


    The Bonide guarantee (see: ”the 1920’s”):

    https://bonide.com/about-bonide/


  • Sunny Mississippi 8a
    last year

    Moses I gave away my Quietmess to a local rose lover this year. After two years I couldn't stand the black spot, mildew, and bare naked sight of that twig. The flowers were unbelievable. The form! The fragrance! I still look at my pics and miss her. But the friend I gave it to already had one in her garden, plus she sprays. I never sprayed mine and it never forgave me. I had a few beautiful flushes each year, but know it's in a better place now. I absolutely have no regrets about trying it and I do thank you for the recommendation. I just ordered Mountain Music, so maybe that Buck rose will do no spray. We shall see!

    I'm also excited to hear Bliss performed well for you. I'm always on the lookout for fragrant, no-spray roses. Thank you for the update!

  • Sunny Mississippi 8a
    last year

    I also gave her my DeeLish since I had results similar to your after two years of no-spray. Hopefully she was able to resurrect it.

    I hope you have a local rose friend you are able to rehome your lovelies with this fall or whenever you decide to move them.

  • jim1961 / Central Pennsylvania / Zone 6
    last year

    I grew Plum Perfect for a couple years moses..Growth rate was slowwww here... PP also had disease issues so had to get rid of it...

    I think PP enjoys warmer temps...I remember PP responding more here when the temps soared high...