Is something killing my roses?

May 18, 2012 10:01 AM

My rosebushes were robust 2 weeks ago, but something's going on. Here's what the worst one looks like from afar and a closeup.

Is it terminal? If not terminal, what can I do to fix it?

posted by buggzzee23 to Home & Garden (4 answers total)

Best answer: Looks like blackspot. I would remove all leaves showing signs of the disease, spray, and treat with an antifungal that you apply at the base of the plant. You may need to prune it severely and let it grow back. You will need to remove ALL diseased plant matter, including dead leaves around the bases of all the plants. Make sure to apply an insecticide, too, because your roses are very stressed and vulnerable right now.
posted by tully_monster at 10:13 AM on May 18, 2012

Best answer: Yup, that's blackspot.

You'll need to strip all the affected leaves and then spray the whole plant with, well, something. There are a lot of options depending on how nuclear you want to get. Just make sure you spray the top and bottom of all the remaining leaves AND the stems.

Here are some recipes for sprays you can make at home fairly easily. Good luck.

If the plants don't recover well, replace them with resistant strains. Then you can be lazy about it like me.
posted by bq at 12:39 PM on May 18, 2012

Response by poster: Thank you. These roses were my late grandmother's pride and joy, so I'll be doing all I can to salvage them.
posted by buggzzee23 at 2:17 PM on May 18, 2012

Best answer: It's really important to only water roses in the morning, and let the soil dry between waterings. Be sure you are not using high nitrogen fertilizer on them as well, because that is like a magnet to pests and pathogens.
posted by oneirodynia at 5:06 PM on May 18, 2012 [1 favorite]