My roses are blooming and very pretty, but the leaves are turning yellow and have black spots. Would someone identify this and also tell me how to take care of them -- preferably with an organic solution?

thanks TD

-- TD Matheny (theny@intrex.net), May 05, 2002

Answers

Your roses have black spot, a very common fungal disease. I have good luck with neem oil, which I use on a weekly basis. I work for a garden center and our roses are looking gorgeous right now. The neem is also effective against powdery mildew and aphids. It is a natural insecticide, fungicide and miticide. Smells awful,and don't use it on a sunny day. I wait for evening.

-- melina b. (goatgalmjb1@hotmail.com), May 05, 2002.

It is mold on your leaves, I do not know to fix this organicly but there is a spray I use that keeps fungus,mold and bug off my leaves. I am unsure of the name but if you chose to use it just ask someone at a nursery they will know. Jennifer

-- Jennifer (jfisher4midsouth@rr.com), May 05, 2002.

TD, in our area you just have to spray your rose bushes before and during the heavy spring rains, and also because of the amount of dew. Are your plants planted in full sun? Roses do poorly in shade, unless it is just dappled shade from very tall trees, they not only need lots of sun, but good air circulation. I have given up on having the beautiful roses I had in San Diego, here in the humid woods :( Vicki

-- Vicki McGaugh TX (vickilonesomedoe@hotmail.com), May 05, 2002.

Get antique roses. They are less susceptible to black spot.

-- Rose (open_rose@hotmail.com), May 05, 2002.

Yup, blackspot fungus. I quit spraying for it as it didn't seem to help much, maybe I will try the neem next time but I just try to manage it.

Keep all the rose debris cleaned up under your rose bushes, all the the fallen leaves. I remove the affected leaves from the bush and burn them.

During the growing season, plant low growing annual flower covers at the base of your roses. It acts as a mulch and prevents fungus spores from splashing in the rain up to the bush. In the off season, use a low mulch and dispose of it come spring in the burn barrel.

Feed your roses heavily and they should outgrow the fungus. and nver water in a way that splashes up to the leaves.

-- Laura (LadybugWrangler@somewhere.com), May 05, 2002.

I LOVE roses, and so did my late beloved Alpine jackie. I decided when we bought our farm in VA I was going to have beautiful flower gardens and rose gardens. So over a period of 2 yrs I had 150 hybrid tea rose bushes and several tree roses I ordered from jackson Pekins. Well, Jackie ate them all, she was a true escape artists until we put electric with the woven wire, still that didn't stop her, but cattle panels did.

For the fungus, here is a tip I got from one of my gardening books, mix equal parts of hydrogen peroxide and water, add a few drops of dish soap, it clears it up.

-- Bernice (geminigoats@yahoo.com), May 05, 2002.

I read in Organic Gardening a few years back that a 9/1 ratio of water to milk sprayed on plants (make sure and get the undersides of the leaves too) prevents and controls fungus, molds, and mildews. I tried it - it works! Have used it on everything from pole beans to english peas to cucurbits to my roses, with excellent results. It works better than the chemicals, and no poison!

-- Joe (botaur2@yahoo.com), May 06, 2002.

Black Spot Remover Tonic 15 tomatoe leaves,2 small onions,1/4 c.of rubbing alcohol Chop leaves and onions into finely minced pieces and steep them in alcohol overnight.Paint the brew on the top and bottom of infected rose leaves.

-- Pam (pams65@hotmail.com), May 06, 2002.

Wow, I just learned a whole bunch!!! I gave up on anything but antiques cause of all the disease and I wanted to be organic. Must plant a couple this year and try these remedies!!

-- diane (gardiacaprines@yahoo.com), May 06, 2002.

I just read that yellow or gold roses are more susceptible to blackspot. Has anyone noiced this?

-- vicki in NW OH (thga76@aol.com), May 06, 2002.

Black spot on roses an organic spray(well maybe not organic but at least not funginex)is the Cornell mixture of 1 tbs. Listerine and 1 tbs baking soda to 1 gal water. Nothing will clean up infected leaves (even toxics)all you can do is to keep new clean leaves clean.

-- John in Mn. (nospam@mywork.com), May 06, 2002.

Thanks to all of you who offered suggestions for black spot. Everything from neem oil to listerine and lots of really interesting remedies in-between. I may try them all!

-- TD Matheny (theny@intrex.net), May 06, 2002.

ms. matheny, organic control of 'black spot' on roses is being achived at even big fancy public arbors w/ a h2o & backing soda mix, [even in orgon where black spot season is year round!] sprayed on before & during the weather that encourages the mold to grow.

i don't remember the proportions but i'm sure you can google.com it for specifics. i have two bushes that fall prey to it but they are tough older types so they rebound quickly so i gave up the intensive management, since it is primarily a cosmetic issue. :)

-- bj pepper ,in central MS. (pepper.pepper@excite.com), May 07, 2002.