Hi, i have never had much luck with roses. Almost every rose i have ever tried growing has gotten this. They are doing fine and then suddenly the leaves get these yellow blotches and what looks like green branching pattern spots on them and all you have to do is touch them and they fall off. Does anyone know what this is?
Hi.
It's nothing serious, it's just blackspot:
https://www.google.com/search?q=blackspot+on+roses&rlz=1C1KAFB_enUS613US613&espv=2&biw=1280&bih=709&source=lnms&tbm=isch&sa=X&ei=s2mcVPfKNIubyQT7yIGwAw&sqi=2&ved=0CAcQ_AUoAg
It is caused by a fungus, and it can be prevented. This is what you do.
Remove all black spotted leaves from the plant AND the ground. Get rid of them (not in the compost pile!) If you don't, your plant will continuously be reinfected.
Water only in the morning, not at night. Nighttime watering keeps roses wet at night - fungus loves that. When you do water, try to keep the leaves dry, since I would guess that your climate is hot and rather humid. If you like, you can use soaker hoses. That's what I do.
Get some elemental sulphur. A liquid concentrate. Don't buy a dust - it's hard to control the application and you don't want to breathe it in. It also controls mildew, leaf spot and rust. It's organic - great stuff that doesn't harm Your hardware store or garden center will have it. Bonide and Safer both make it. Get a concentrate, so you can dilute it yourself. A bottle of concentrate lasts years. 16 ounces is plenty.
http://www.sears.com/safer-brand-garden-fungicide-16-oz-concentrate/p-01298667000P?sid=IDx01192011x000001&kpid=01298667000&kispla=01298667000P&kpid=01298667000&mktRedirect=y
Use the spray with a pressurized spray bottle. Your hardware store or garden center can help you with this too. They only cost about $10, but you can prime them and they discharge a steady stream:
http://www.amazon.com/Pressurized-Handle-Sprayer-Bottle--Capacity/dp/B00AMRS4MC/ref=sr_1_5?ie=UTF8&qid=1419537520&sr=8-5&keywords=spray+bottle+pump
Spray your roses top to bottom, (get the bottom of the leaves!) but only when the temperature is under 80 degrees. Do it every ten days or so (this is a guess).
I have 32 roses. Not all of them are prone to blackspot, so I just treat the ones that are. Again, all of these measure are preventative, although if you remove all your leaves and spray now you can avoid black spot through the end of the season, and your roses will re-leaf.
Does this help?
Donna
Yes!! Donna!! Thank You soooo much. I will try to get the elemental sulphur . If i cant find it here in DR, i will order. Its incredible this Black Spot. It was raining all day today and with one day of rain all the leaves in one of my roses turnednyellow and are falling off!! It is very humid here. I live in the mountains so it is not that hot, mid twenties at midday and mid to low teens at night. Thats celcius. :-) , but very humid.. Thank you soo much . Ill let you know how they do.
BTW Donna. Do you know the name of this rose? Nurseries here dont use scientific names or hybrid names. All the roses are clumped together and their all just roses. You pick the colir but know nothing about the particular needs of the type. This is the first one i have seen here that has hips.
It looks like Rosa canina to me. What do you think?
It's something related to it, I think. Rosa canina often has bright red hips. But it's very pretty!
I just found this: I wrote it down some time ago. It has the measurements for the use of sulphur:
Directions for Use:
1. Shake Well
2. For control of blackspot, leaf spot, and rust, mix 1 part concentrate to 30 parts water or 4 fl. oz (8 tbsp) per gallon of water.
3. For Powdery Mildew, mix 2 fl. oz (4 tbsp) per gallon of water.
4. Place about half of the volume of water in sprayer, add concentrate, stir well, add rest of water and mix thoroughly.
5. Spray plants thoroughly to wet the upper and lower surfaces of foliage. Repeat as recommended.
Hi, I just became a gardener with my own yard so I'm new to this so to speak. This is my first spring with roses already in the ground, got them planted June through Sept of last year so I guess you could say they are mostly 1 1/2 years old. Recently, I purchased neem oil for black spot, figured out what it was just before winter hit...anyway, I cut off all canes that had brown spots or any leaves that looked yellow or spotted and threw them away. Is this okay to use, too? I've purchased so much that now I'm not sure what to do with what in a sense. Hated to go back to store and get another item if it wasn't a necessity. I am determined they are going to be pretty one day so I will get the elemental sulfur if neem oil is a weaker product. How often do you recommend spraying for black spot and how soon do you start? I live in NC close to the coastal area.
Thanks for reading!
I spray with black spot at the beginning of my season as the roses are breaking dormancy. I do this after my initial pruning. Then, if it is damp and conditions are ripe for blackspot, I repeat every month.
Mind you, I only spray roses that actually get black spot. Some roses really don't. I have a couple of Bourbon roses that are black spot prone, so they get sulphur. But I have some bulletproof plants, like the polyantha Marie Pavie and the Earth Kind shrub Sea Foam, and they are not sprayed.
I never found that Neem oil worked for me. It may just be me.
I didn't think we even got black spot in this area until my neighbor moved in about 8 years ago. They immediately planted roses across their front porch, and haven't pruned them properly since. The one that hangs over my driveway is disease prone, and the afternoon breeze blows that way, so I have had to give up roses in my back yard. I would send this thread to her, but she (A). wouldn't read it, and( B) wouldn't do anything about it if she did. We do get a marine layer at night when it's cool, in spring and fall, but it can be managed with proper care. My roses in the front flower bed do great, in spite of crowding.
Oh, yes, blackspot spores fly through the air. Nice. People who stick plants in the ground and don't take care of them are annoying. Do some research and get roses that are not blackspot prone. I have 34 roses, for goodness sake, and I only have to treat two of them.
I have a neighbor who put aggressive, invasive plants on my side of his property so he wouldn't have to maintain it - ditchlilies and goldenrod and the like. Stuff that grows wild on the trails. Ugly, but he can't see it. I dug them out, out down a layer of mulch and regularly spray it with Roundup.
He allows his ditchlilies to grow more than three feet onto a neighboring property, right under the fence. The neighbor keeps mowing them down, but they are spreading. Round up doesn't work on the. You just have to be persistent about removing every bit. Which I did, but it was a lot of work.
Some people, pardon me, are just inconsiderate idiots.
This subject has probably been beaten to death and I've probably read TOO many articles. I can't seem to get the hang of treating roses. I have two miniature roses in one of my gardens. What I thought was blackspot on one.. not sure anymore.... the leaves aren't yellowing, they had/have lil brown purplish spots all over them. I didn't think the disease season arrived before hot and humid arrived as I live in NC... but something is going on with one of the min rose plants. I've treated them with Neem Oil, elemental sulphur and Bayer Advanced 3-1 which is said to be systemic. Tonight I read that I shouldn't use the 3 in 1 only Bayer Advanced Disease Control. Sigh. I don't really know what to do anymore to make sure I'm using the most effective. I just used the 3in1 2 days ago...now do I go and respray with the Bayer Advanced Disease Control? I have heard that I shouldn't use the same thing over and over...need to alternate. I love roses but it's hard getting the hang of it. The rose with the brown purplish spots is losing its leaves. If I can get ride of whatever is causing it, will it generate new growth this season?
Also, one more question. I have been trying to keep a routine of using Epsom Salt. But it doesn't dissovle in cold water? How do you apply Epsom Salt to a plant?
Thanks in advance for any advice.
Epsom salt is a source of only 2 elements that plants need. Have you tested your soil to see that it is really lacking magnesium?
If you are applying Epsom salt frequently you are OVER supplying those 2 elements (magnesium and sulfur), and there may be marginal deficiency of the elements you are not applying.
Epsom salt is advertised as a miracle cure for plant problems.
It is not.
It is very helpful for plants growing in magnesium deficient soil.
It is of very limited use in soils that have enough magnesium.
It can be toxic if the soil already has a rich supply of magnesium.
I apply Epsom salt this way:
Scatter it lightly ONCE in the area the plants will use it (root zone under shrubs and trees, or apply to the whole vegetable bed once a year). Yup- apply it dry. Watering will dissolve it a little bit at a time, making it a sort of slow release.
Apply other fertilizers that contain the other elements plants need so they are supplied with a balanced ratio of all the elements they need.
I am applying the Epsom salt and other fertilizers in a way that just replaces what they are taking out of the soil. Not applying excess.
Post pictures of the roses that are losing leaves:
On the close ups, remove the leaf from the plant and place it on a neutral background. Perhaps a sheet of paper, or the ground will work, if it is a uniform color (plain ol' dirt- not multicolored mulch)
1) Whole plant, perhaps from several angles.
2) Several leaves showing
a) Healthy (or nearly healthy)
b) Problem just getting started (might be just a few speckles, or slightly mis-shapen leaf, slight discoloration)
c) More advanced, but not quite ready to fall off.
d) Fallen leaves.
3) Repeat (2) with pictures of the backs of the leaves.
4) Repeat, getting pictures of the leaf and flower buds if they are showing any symptoms of anything.
If the leaves look like there are several issues going on repeat the series, target each problem. Different diseases or pests can leave distinctive signs such as the shape of the damage, and any discoloration around to worst damage.
Basic treatment protocols:
1) Know what you are treating, and its life cycle in your garden.
2) Treat with the most efficient product at the optimum time for your garden.
by treating at the optimum time for the pest or disease you are knocking back the population before it has a chance to build up. This can include fall clean up sprays to minimize the pest population when it is getting ready to overwinter. This usually includes a treatment (or several treatments) as the weather warms and pest and disease organisms are spreading out from their winter dormancy.
But the material to use and timing varies with the pest or disease being treated and the weather in your garden.
In answer to the pests and diseases from the neighbor's untended plants:
1) Cut them at the property line.
2) Spray them as needed, from your side. Just the parts that are closest, and might be explained as over spray ("Well, I am sorry your roses are doing better in that area, I was spraying my Euonymus for powdery mildew- it must have killed the black spot on your roses")
3) Plant something that will slow the wind before it gets to your roses. Hopefully most of the disease spores will drop out onto that screening plant. Make sure it is not a host for pests or diseases of the roses.
