Have you had a lot of rain? Usually yellow leaves is an indication of over watering. Older leaves may also turn yellow and drop but I have never seen a rose do it to the point of having no leaves unless untreated blackspot is the cause. I found the attached link with some good information.

Liz

Here is a link that might be useful: reasons for yellow leaves

This happened to me. I have about 14 mini roses and all healthy. Last week I went out to check on them after a three day rain and one bush looked like it had been stripped. I could not find any insects, some of leaves yellow but most not. Now I have green sticks with just a few leaves on the ends of this bush. Oh...it was Spice Drop that dropped it leaves!
Linda

Hi Linda, Liz,

Well, I guess we had a lot of rain. The weird thing is, I have Montana right next to Orange Frenzy and Montana is fine, but Orange Frenzy isn't. I didn't see any blackspot, thing is -- some of the leaves did turn yellow, but some didn't -- they dropped off the plant when they were green!!

So maybe I should try to improve the drainage for the roses that dropped their leaves, in case that's the issue. How do I do that?? Will read up on it. In the meantime, orange frenzy is hanging in there with lots of green sticks and only 2 leaves. I keep talking to it...

Deb

Deb

I have found that it really depends on the rose as to how much they can stand "wet feet". I have some that are fine and other that will start to show yellow leaves after real heavy rains. (Like the 3" we had in 1 day last week)

I would think improving drainage after the roses are in the ground is not easy. I would contact your local garden center to see if they can recommend anything for established beds.

You may also want to jump on the regular rose forum and see if anyone in your area has been having the same problem.

Liz

Thanks Liz, will do. Went out there the other day realizing that the roses that are having trouble are all in the same area, looked closely, and --- see black spot on the roses (the fallen leaves, and some surrounding roses) all over the place. So, maybe it was blackspot... have to check to see if blackspot will make all the leaves fall off (am really learning as I go!!!...)

and hoping all those lovely green sticks which is all I have left of orange frenzy, produce some leaves again...!

Debbie

Debbie

As long as the cane(s) are green your roses are still alive and well. And you should have enough nice weather left for the leaves to grow before your first freeze. I would also feed half strength of fish and or seaweed emulsion. I use it to feed new baby roses and it really helps.

Liz

No mention of spider mites Mites of course like hot dry weather. They will suck the juices of a leave and cause the leaf to turn yellow. To check, take a piece of white paper, hold it uner a leaf and tap the leaf with a pencil. If you have mites you will see them moving on the paper.
Mites start on the bottom of the plant and work up. I had a mico mini defoliated because of them.

Went to the garden store and met this quite pessimistic (but nice) staff person who basically said roses have so many problems, and do you really want to deal with all of them..? Since I didn't go in asking THAT question, I just took a pass on it, and asked, how do I get rid of blackspot..? After he told me, nothing works, he did suggest that I buy this product -- lime sulphur -- soak the soil with it, and said that it would end the cycle, since blackspot remains in the soil through the winter. So I did that. However, I haven't checked for spider mites! Will do that, PLUS buy some fish emulsion. good idea guys! The affected roses are now orange frenzy, constellation, vista, sunset, and a couple of others nearby are thinking about losing their leaves too. I can just tell. But I am remaining cheerful, determined to conquer this problem... have a good day everyone...Deb

There are some endemic options for rose diseases or pests. Endemic products usually can be sprayed on plants or fed to plants in the form of granules or liquid. The absorbed fungicide (good for blackspot) and insecticide will travel throughout the plant, protecting all stems, leaves and flowers from disease/insects even if the soil is contaminated. The effect will last 4-6 weeks and will not wash off with rain or watering. These endemic products can be expensive, but I've had some good results at half strength (or less) but more frequent applications--if needed.

If you go with an endemic fungicide/pesticide be sure to protect your skin, pets, ponds, etc. These products are powerful. Also be aware that some are mixed with a fertilizer, and you may not want to fertilize your rose bushes too close to their period of dormancy.

With 90+ mini roses, I'm sure we can learn a lot from your experiences/techniques. Good luck!

Debbie

Such a shame the garden store was so negitive.

The best thing I have found that is easy to buy to keep black spot under control is "Disease Control for Roses, Flowers & Shrubs". I get mine at Lowes. I spray every 10 days and it keeps it under control. I would hesitate using a lot of lime sulphur. It may kill the spores in the ground but not on the roses. Spider mites are easy to find as you will see fine webbing on the under side of the leaves. The best thing to get rid of spider mites (and aphids) is a blast from a water hose.

Liz

Blackspot is a fungal disease, and yes, once a plant is infected, it can cause all of the leaves to fall off. It affect the leaf's ability to perform photosynthesis. Some varieties are more resistant to blackspot (you'll hear the term "disease resistant", the "disease" referred to is usually blackspot). That's why some get all spotty and drop leaves right away, some just get very spotty but hold on to leaves and some might get a spot or two but leaves stay green and don't drop.

Lime sulfur in the soil won't help. The disease stays on leaves and canes. Using a fungicide like the one Liz uses (Bayer Advanced Disease Control for Roses, Flowers and Shrubs) on a regular basis will help the plants resist an outbreak of blackspot. You can start now, but note that the blackspots on the leaves don't go away. Next year, start your fungicide application right after pruning, and continue through the season (usually through October here).

Lime sulfer can be used once or twice in late winter (I think temps have to be in the 40-degree range) as a dormant spray to help control any blackspot that may have overwintered.

Ditto on the check for spider mites.