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lyannastarknola

About to cave and spray for blackspot. Talk me down? Enable me?

7 years ago

All of my roses are babies, the oldest are about a year. Losing a few leaves to blackspot on a fully grown plant is not a big deal, but when they're only a couple of feet tall I'm scared the new growth won't be able to keep up with it and they'll just all be sad naked sticks.


So while they're tiny, I'm thinking I'll spray. Just for disease, not for pests, with the go-to Bayer stuff. What's your experience with it? Is it worth it? Do I need to keep the cat away? Will it chase away good bugs? Does it actually work? I don't think I'll ever get them completely clean, but I don't want them all sad and defoliated before it's even actually technically spring.


What made you decide to spray/not spray?

Comments (37)

  • 7 years ago
    last modified: 7 years ago

    I just bought Serenade online. It seems to be safer. I got tired of all roses being sticks. I also used neem oil....but it only worked half the time.

    lyannastarknola thanked kaleidoscope eyes
  • 7 years ago

    Of course you should spray if you want to, but, given the way you phrased your post, I'm sensing that maybe you don't!? In that case you might be as interested in this article as I was: https://www.telegraph.co.uk/gardening/how-to-grow/at-last-roses-meet-their-perfect-match/

    In addition to picking off/picking up black spotted leaves during the course of the summer (it can be a pain with big roses, but for babies it is much more doable) mulching to cover the blackspot spores from last year helps. I wonder if the type of mulch matters. Here in the PNW we have a lot of cedar mulch. My roses do get black spot (I do not spray) but never to the point where they fully defoliate (even the young 'uns) so maybe the cedar mulch helps? Of course, your climate (and your strains of black spot) are totally different from mine, so who knows!

    One thing I do worry about with spraying for fungal disease on roses is the possible impact of fungal treatments on beneficial fungus in the soil. But there is no perfect situation, and in the garden (as in life) we are always making trade-offs. In the end, it all works out, somehow.

    lyannastarknola thanked K S
  • 7 years ago

    One doesn't need to use a commercial fungicide to control blackspot. A milk spray (2 parts water, one part milk) sprayed before you see any signs of disease and then weekly or every 10 days should keep it at bay. The lactoferrin in the milk is antifungal and the lactic acid changes the pH of the surface of the leaf, making it inhospitable for fungal spores. I find that neem oil also works very well for this purpose.....it has natural fungicidal properties.

    lyannastarknola thanked gardengal48 (PNW Z8/9)
  • 7 years ago
    last modified: 7 years ago

    Like you, I'm just antsy about upsetting whatever invisible ecosystem is happening. I don't mess with the bugs but who knows what kind of awesome fungus is doing some sort of invisible good down there? Not me! I've been pulling off the spotted leaves, but there are only so many on a 2-foot plant and that's what makes me worry I'm just ripping them apart to nothing.

    I just put down another big fat layer of pine straw mulch - it's pretty, cheap, and termites hate it, plus most of the roses are going into the ground for the first time, so hopefully the spores aren't a thing. Yet.

    I always knew blackspot was pretty much a certainty, but it dug its heels in way earlier than I thought. We had 14 80+-degree days in February! Which was actually wonderful for me but the BS has definitely gotten a head start, ahead of the actual roses.

    Most of them are leafing out like mad but I worry they can't keep up. I apologize to my little SdlM every time I rip a leaf off. It's for your own good! You'll be fine! You're beautiful just the way you are!

    ETA that I should probably shut up and buy a bunch of salvias as well. My underplantings/etc are all first and foremost attempts to get mosquitoes away from me, but there are no shortage of salvias around here. They're pretty and easy and love the heat so it's kind of silly I haven't done that yet.

  • 7 years ago

    Oooh fun trick, gardengal! Definitely worth a shot, thank you.

  • 7 years ago

    I have quite a number of hybrid teas and I have been spraying with bayer fungicide from the beginning. I would rather not spray at all, which I tried one summer. Unfortunately this did not work out and by the end of July, my poor roses where completely covered with blackspot and some where even defoliated..


    Now, I'm just careful to try to not get any of the spray on my body, and after I finish, I take a shower and change my clothes. Just be thankful that you don't have rose midge like I do; it sucks:(

    lyannastarknola thanked Streisand Fan
  • 7 years ago

    Also remember that roses often outgrow their BS vulnerability as they age. Once they bulk up & get some good roots under them it often goes away or is easily managed without spraying ie; picking the leaves off. I have quite a few that took 3 years or more to outgrow it. Of course, buying roses with great disease resistance helps but oh, there are so many beautiful roses that BS in my climate.

    lyannastarknola thanked smithdale1z8pnw
  • 7 years ago

    I have found that many of my BSers shape right up once planted in the ground. Pot culture can be difficult and can cause stress which, in turn, makes it more likely for the plant to get disease, etc.

    lyannastarknola thanked Vaporvac Z6-OhioRiverValley
  • 7 years ago

    Thanks all! I will keep apologetically yanking leaves for the moment. Looks like 65-75F (you know, actual spring) for the next couple weeks so that might help the leaf growth outpace the blackspot. I just don't want to be pulling off leaves faster than they can put them out!

    I mostly did my homework about roses that were disease-resistant around here, but I also know there's no such thing as disease-free, especially in the hot humid south. I was just thinking they'd have a few more weeks to grow and sink their toes in first!

  • 7 years ago

    Streisand Fan, I still don't really know what I'm in for, but from what I hear I can't rule out chilli thrips, which is the stuff of nightmares. I'll take blackspotted naked roses over any sort of tiny nefarious superbug any day!

  • 7 years ago
    last modified: 7 years ago

    The Bayer fungicide works very well for me.

    Every year is different in the severity of black spot pressure, but if you garden in 'The Black Spot Belt,' you can be sure you will battle it to some degree every year.

    Young roses are just that, young, like little children. They develop their strength/disease resistance as they mature, needing help until they reach maturity.

    My advice is to begin a spray program, but stretch out the length of time between sprays to see how little spraying you can get away with, yet keep the foliage healthy enough for your baby roses to thrive and put some size on.

    You may find that every 3-4 week sprays work well. Still, I would start with every 10 day to 2 week sprays at first. Since black spot starts at the oldest, lowest leaves on stems first, and spreads upwards, if you concentrate on the lowest, oldest leaves, you may find that the entire bush may not need to be sprayed, just the older, lower ones.

    The jury is out on the effectiveness of Serenade. It is an organic control, but it must be applied frequently, and after every rainfall.

    If I live long enough to see it, and the trend continues, black spot proof/resistant rose introductions in the desired large, fragrant bloomers, may make black spot a disease of the past. For now: the Knockout series, Earth-Kind Roses (which program seems to have tanked), ADR roses, and roses from here and there that through word of mouth or through personal trial and error show acceptable black spot resistance, are all we have available to keep a no/little spray rose garden.

    Roses are expensive, and labor intensive, but we are thrilled by their blooms! Unfortunately, disease control at some time or another is required.

    Moses

    lyannastarknola thanked Moses, Pitt PA, cold W & hot-humid S, z6
  • 7 years ago

    Thanks, Moses. I often lament my small yard and the necessarily small number of roses I can reasonably fit into it, but one advantage is that even at my laziest, I should be able to stay on top of these things and make sure everybody is healthy.

  • 7 years ago

    Environment and health of myself and my family are great reasons to go no-spray.

    Henry is atypical for his generation. Most folks that age grew up with a fairly cavalier attitude of, "that's what the chemical corporations are for." Having a father educated in the field probably helped. (I lost my dad to a neurodegenerative illness that was apparently exposure related.) At the height of the HT craze, there was virtually no regard given for health in breeding roses, and as for the chemicals, in the U.S., the burden of proof seems to lie on the regulators, and not the chemical companies. (Just look at the current fiasco involving Monsanto in the courts today.)

    Radler and Kordes roses, as well as some of the newer hybrids from younger hybridizers, have a lot to offer in terms of resistance, but even for the Kordes roses, you often have to turn to the German website to get objective evaluations of their resistance. Americans are not as conscientious as the Germans, it seems.

    Chemicals upset the natural balance too. I was shocked many years ago to learn that I had fewer insect pests when I let mother nature -- predator/prey -- address my issues. It was truly remarkable, and I have butterfly larvae to thank for the restraint that really opened my eyes one year. The assassin bugs moved in on the caterpillars, and addressed a host of other ills while lacewings, syrphid flies and others addressed the smaller pests. Sure, I had a couple months of issues while the system worked itself out, but ultimately, I had a much healthier and more productive garden for it, and some of my worst chronic pests were never again seen after I quit spraying for them.

  • 7 years ago

    I definitely leave the bugs alone. They have it all figured out. If pests are there long enough, the beneficials eventually show up. Or, as in the case of passiflora, I just admit defeat and move on - the fruitillaries always find my vines, but the past couple years they've defoliated them before there's a single flower. So hey, that's just not a thing I grow anymore! Easy peasy. I probably just need to give the roses a little more credit. They're babies, but they know what they're doing.

    Stress is the opposite of gardening. A few dead leaves here and there, I can handle. If anything becomes a constant fight, it doesn't belong in my yard and no hard feelings. That approach has worked pretty well so far!

  • 7 years ago
    last modified: 7 years ago

    Once I quit spraying several years ago, these little guys started showing up in droves. They eat up lots of bugs. Oddly I haven't really had thrips since they arrived. They hide in the rose flowers and other flowers and keep stuff clean.

  • 7 years ago

    Look at that little guy!!! Make yourself at home, buddy! We don't have any frogs, but we do have a little pond that's a toad factory. (We call them Modem Toads because during mating season they sound like an old fax machine)

    I suspect the little green garden lizards and dragonflies do a lot of heavy lifting for us in the summer as well. The longer I keep my little ecosystem functioning, the better it will work. In theory!

  • 7 years ago

    True. Dragonflies are one of the reasons we hardly have any mosquitoes. All our neighbors spray spray spray they wonder why they have gobs of mosquitoes and we don't.

    spiders are good too

  • 7 years ago

    I won't live with black spot. Thus I will spray to keep it at bay. I have visitors to my garden all the time. I also take care of a garden at the local news paper office and a good size garden at my church. People appreciate a good looking bush to go along with the beautiful blooms. I use safer soap for aphids.

  • 7 years ago
    last modified: 7 years ago

    I live in SE TX that is black spot heaven. I started off spraying about 5 years ago but started reading this forum and got some great advice......feed your soil with plenty of organic materials, good soil helps your roses grow strong and healthy and I have found by not spraying my roses they are able to fight off black spot, it's like they have built up their immune system. I'm not saying I never get bs on some of my roses, but when I do it's very minimal and doesn't bother me. I usually pick off the leaves and they look fine. It really is a personal decision that you have to make for yourself and how much bs your willing to tolerate.

  • 7 years ago

    boncrow, do I remember correctly that you used to live in Cajun Country or am I making that up? Either way I always pay extra attention to your comments because you're probably the closest climate to mine. I do think you're on to something there with the "immune system" thing for sure, and it's all about feeding the soil. Good soil, healthy plant.

    Ken, if I were maintaining a garden that would be viewed by anyone outside of my immediate household or possibly neighborhood, I would almost certainly have been spraying (and weeding, and feeding, and pruning, etc) since day one!

  • 7 years ago
    last modified: 7 years ago

    I spray regularly for blackspot, and thrips, and Japanese Beetles, it is the only answer for my area if I want to stay with the susseptible varieties that I love. I always wear a tyvek suit and respirator, gloves, glasses, etc. i always spray near sunset to reduce killing bees. Someday, I may change to more earthkind varieties and quit spraying, but it's not in my current plans.

  • 7 years ago

    Al, where do you live. I noticed on your page you're in 5b and like roses for shade. I'm curious which you grow. Sorry for going OT, but it could still be useful info for this post. : )

  • 7 years ago

    Vaporvac, I definitely agree that rose selection and climate make a difference. I grow mostly Teas, Noisettes and Chinas, and they do blackspot- especially when young- but I've never had one defoliate and die, and no- we have a dog, so I won't spray. I've heard Jeri's stories about her dogs' health issues when they used to spray their roses.

    Virginia


  • 7 years ago

    I do live close to the Louisiana border, close to Lake Charles so we have a very hot and humid summers. I agree Vaporvac and Virginia that rose selection is also key, I have a variety of teas, polyanthas, bourbons, noisettes, floribundas, Austins and a few HT's. Not every Rose is a hundred percent clean all the time but I do have some that are standouts and never have BS at all, right now Peggy Martin and Eutin are the ones I can think of that never bs for me, there might be a few more but I can't remember lol.

  • 7 years ago

    Sultry what do you do about chili thrips? I used to not spray until the chili thrips showed up but if I don't spray Conserve all my roses would die. Although I only spray twice a year max, it seems I have less wildlife in my yard, which I really enjoyed.

  • 7 years ago

    I am legit terrified of chilli thrips, like I’m all “live and let live, nature finds a way” etc up and down this thread but I’m scared to death of those things.

  • 7 years ago

    Darlows Enigma, Rose de Rescht, Knockout, Home Run, and Cuthbert Grant are all in part shade and doing well.

  • 7 years ago

    I haven't had any chili thrips in my garden yet. I am in NE FL not sure if they are here or not but I haven't seen them. I used to have tons of regular thrips every spring. Once I quit spraying, and the little frogs and other good bug populations increased, the thrips went away. I see aphids and other stuff and they get quickly eaten.

  • 7 years ago

    As far as I can tell I don't have chili thrips in my neck of the woods and fingers crossed I won't. I love it when I see lady bugs because I know they are going to munch on the aphids. I stopped spraying several years ago because we have pets that are outside in the yard when we are outside and we have tons of birds that hang out and have their babies in my yard and they feed the little ones insects and worms from my yard plus other wildlife like bald eagles and owls that fly around and I don't want to mess up their eco system of food and prey.

    lyannastarknola thanked boncrow66
  • 7 years ago

    You guys are lucky, chili thrips are evil. I think I unknowingly introduced them into my garden when I first got interested in roses and bought some scruffy looking ones at Houston Garden Center. I didn't know what I was looking at and brought them home.

    lyannastarknola thanked humble5zone9atx
  • 7 years ago

    I’m concerned it’s only a matter of time, especially since I don’t have a local source for roses. I am proud of my little ecosystem but these things are pretty much aliens. There’s no balance because they’ve only been in this hemisphere for like 20 years. 20!!!

    The very first sentence of the Wikipedia entry calls them an “extremely successful invasive species” which is the kind of almost-editorializing that cracks me up/fills me with dread. So you know. Fungus, aphids, sure. But chilli thrips are a whole different deal and I am quaking in my cute shiny red gardening boots.

  • 7 years ago

    We have this debate all the time. I'm not sure there is a right or wrong answer. You have to decide for yourself what is acceptable.

    There is a school of thought that says by spraying you throw off the ecological balance of many things in the garden and that in turn eventually leads to even worse infestations of diseases and insects. By not spraying you allow the garden to reach a balance that, while it doesn't eliminate it, does keep it in reasonable check.

    I've learned to lower my expectations of perfection and enjoy my lovely blooms even if they aren't picture perfect all the time.

  • 7 years ago
    last modified: 7 years ago

    There's an old saying...an ounce of prevention is worth a pound of cure. I would try the milk spray that gardengal suggested. That should keep black spot levels at a minimum if done correctly.

  • 7 years ago

    Good for you Seil!

    after all, other things that inhabit the earth have a right to life as well as we do. And my experience with an organic garden has been very positive, the plants thrive and grow stronger, the birds flock here, and balance is achieved. But, I hope that if a gardener must, must spray, they will tell people, or post notices to that effect. In these days of chemical sensitivity, the least we can do is to be above board about what friends and visitors are exposing themselves to in our gardens, just as we would label anything with peanuts, etc. in it at a pot luck.

    hope you all can get out into the garden today!

    cheers

    claire

  • 7 years ago

    Amen, Claire.

  • 7 years ago

    I spray fungicides. I live near Ken and you cannot have a rose garden in this part of the country without spraying. Unless you are willing to let all the roses lose their leaves. I don't spray for bugs, except for thrips, and that is spot spraying on unopened buds only. Integrated Pest Management is a method where you decide what to do about each issue. Black spot is something we have to be pro-active about here. If I spray preventatively, I will actually spray less than if I waited for the BS to come. I don't want to use chemicals incorrectly. I follow the labels and use caution where recommended. It's a personal choice, but I don't fee that spraying fungicide every few weeks has had a negative impact on my yard. I only spray my roses, The spray goes on the roses, not into the air. I have a lot of other plants in my yard. I have a butterfly garden with bunches of plants that attract butterflies that doesn't get any spray at all.