Yup, it's normal. If you think about it from the plant's point of view ... the rose just doesn't need them any more. They are not providing nutrition. Photosynthesis slows down in roses at about 70F.

Roses, let me re-phrase that, healthy roses typically abandon foliage, canes and roots that no longer serve the plants needs and grow replacements.

Smiles,
Lyn

And the frost and cold weather has probably damaged those leaves by freezing the water in them which expands and breaks down the cells in the leaves. Once damaged they yellow and drop off. When the weather warms back up enough for the roses to start to grow again they'll replace the leaves with new ones. Also, this time of year there is way less sunlight, even in warm climates, so the roses slow down growing anyway. As the daylight start to get longer they'll start to perk up.

We haven't actually had a freeze but it's been colder than usual for this time of the year and a lot of the roses have yellow leaves. Strangely enough, Bonica is the most affected, and it's more sheltered since it's near the house. Only they know what they're doing and why.

Ingrid

Nik......

Most roses without re-bloom are either the species roses originating in colder climates and/or what we commonly think of as ogr roses which were bred using these species. These roses know how to go dormant. They pull the sugars out of the leaves, then pull the nutrients and water molecules from between the cells out of the canes and send them to the root zone. (When there is only one water molecule between cells, it doesn't freeze and expand and burst the cane.) They are genetically programmed to go dormant during the cold seasons for "survival of the species."

This is not true for all once blooming roses ... think of the once blooming teas and noisettes ... the species used to breed these roses and other repeat blooming roses came from warmer climates and never had the need to go dormant, so that process is not included in their genetic make up.

When the repeat blooming gene was introduced into the breeding with the roses that naturally go dormant, they also brought along the genes into the rose gene pool that kept the newer roses from knowing how to go dormant. So, these roses are more vulnerable to the cold.

Our modern roses have a mix of genes of roses that know how to go dormant and those that don't, but typically, the plants abandon the plant material ... generally leaves ... that no longer serve a purpose for its survival and wait until conditions are right to put on new growth.

The ogrs, once-bloomers, in your climate are just following their genetic programming. As a note, these roses are also programmed to have a certain amount of chill hours to thrive. If they don't get those chill hours, they are often total duds in warmer climates.

Smiles,
Lyn

Yeah, Kippy -- While we are now experiencing record-setting high temps (along with this blasted wind) -- we DID have several days of record-setting cold.

I have never seen such a high % of my roses dropping their leaves. None of the Teas are doing it, but some Austins are, and some Hybrid Perpetuals and the like. ("Old Town Novato" and "Benny Lopez" are virtually nekkid. "Forest Ranch Pom-Pom is working on it.)

I'm sorta glad to see it, and I'd appreciate a bit more cold.

Jeri

We are having a pretty cold fall/winter this year, for us. We had a very hard frost in late October, while many of my roses were brimming with buds. Huge disappoint as I usually have blooms up to Thanksgiving.

All of my HTs have lost their leaves. Most of the Austins have. The teas still have some leaves and they leaves they have kept are nice and green. Frankly I wish they'd all loose all their leaves so I didn't have to strip any at pruning time

Interesting too that Renae did not like the frost and had a lot of dead leaves. And Weeping China doll, the old foliage is dead brown and the new bright happy green.

It was about 80 today, so much for cold for a while.

The only roses that had yellow leaves during our short cold spell were my two hybrid perpetuals: B. Prevost and Grandmother's Hat. I was wondering why and now I know. Incredible what I learn on this forum.

On the other hand, my teas are blooming now.

Oh, my Teas are also blooming.

Jeri ...

The reason the teas haven't lost their leaves is that they are the roses that don't know how to go dormant, so they don't pull of the nutrients and moisture out of the leaves when the cold hits.

It took a while for the light bulb in my head to go off before I began to understand the why of it ... lol.

Smiles,
Lyn

Not quite. They CAN go dormant, but they do so in hot, dry conditions. That is how they survive summer drought.

Jeri... you are right. I should have said "winter dormant". Ooops !

Smiles,
Lyn

S'OK Lynn. winter dormancy is what everyone thinks of.

;-)

Jeri

nikthegreek,

I want to apologize to you for the rude welcome you received to your post. At least, I consider it rude to restate something someone (yourself) has said quite well as though it wasn't said correctly or well at all.

I can attest that the individual who responded to your post often feels the need to unnecessarily correct others. I'd like to assure you that we aren't all like that on the Roses Forums, neither are we all xenophobes.

I see that you are new to these forums and I would like to welcome you. I think it would be great to hear your experience with roses in Greece!

I repeat that your post is stated very well for a short post.
And if you are bilingual, you are obviously fluent in English.

Again, Welcome!

Sandandsun,

Once again, these forums are not a platform for you to launch personal attacks. Lyn states nothing which was derogatory nor condescending. She merely gave a scientific and thorough explanation as to what Nik has observed in his experiences. As these forums are here to share information as well as experience, her post falls within the appropriate posting materials. It seems condescending to me that you would assume Nik would be offended by such a post, and that he for some reason has not come by English as a native language alongside Greek.

It would behoove you to refrain from further alienating yourself from this community by way of astoundingly ignorant and aggressive posts. Mind the manners your mother taught you, you are embarrassing yourself.

Nik,

Welcome to the forums.

Lyn,

Ignore Sandandsun. He has repeatedly posted inflammatory, unwarranted attacks on other members. If I were in a position to tell the moderators how to do their jobs, I would have told them to ban him long ago.

Josh

Thanks all for the welcoming wishes, no I did not get offended by any post, everybody has a style of expression and 'talking' in writing can easily lead to misunderstandings thus we all need to be tolerant. English is not my native language so please excuse some errors in expression on my part. Most problematic thing for someone conversing in a forum in a learned language is not the fact that one may make grammatical or syntactical errors but for one to appear using the proper tone without being misunderstood. Cutural differences can often come across as inappropriate mood or tone so I will kindly ask you to be tolerant of me. This often works the other way around also, so if I ever ask for a clarification on someone's post this may be attributed to the same factors. Having said all this, I can now admit that verbosity is a personal fault of mine so I will not be offended if you kindly told me to shut up..lol
Nik

Jeri,

With regards to what you're refering to as 'summer dormancy', living in a med clime I'm very familiar with real summer dormancy as expressed in very many native plants. I would be hesitant to class a rose's summer survival mode as real dry period dormancy although I admit I'm not sure where the line is drawn between the two. I would tend to think that the plants that only grow, flower and fruit in the winter over here express real summer dormancy while the rest just go into survival mode which they would rather not have to do if given half a chance.
Nik

nikthegreek,

I am so glad that you were not offended. I did not want to risk the possibility that you felt unwelcome. To my recollection, I have not read posts form anyone else in Greece on these rose forums.

You and the folks in SoCal probably have much in common in terms of climate. And the performance of roses available to you there and not currently available in the U.S. would likely be a relatively good indicator of the performance of those roses in similar climates like SoCal.

I do not have a Med climate - well, except in the years where the normal el nino/la nina pattern shifts. Those years are very difficult for my roses to survive so I don't envy your climate at all.

There are quite a number of nice folks in SoCal on these forums and I think you and they will enjoy your mutual discourse.

Since my climate's similarities to yours are the exception, I won't be able to contribute anything of much value to those discussions, but I will enjoy reading them.

Happy New Year!

This post was edited by sandandsun on Sun, Dec 29, 13 at 11:18

Nik ...

I am not on the GW rose forums often enough to know who is "new", so let me give you my "welcome", too. It's going to be fun having your voice added to our discussions.

Josh ...

Thanks for letting SAS know that personal attacks are an inappropriate part of posting to rose forums. I tend to think of him as a magnificent rose that adds great beauty to the garden armed with thorns. I do ignore the thorns.

SAS ....

I had no intention of being rude or mean-spirited. I love learning about these things and love sharing what I have learned. I love roses. That's my total agenda.

Smiles,
Lyn

Thanks for the insight about the yellow leaves after the cold temps. I was wondering what had gone wrong. Silly of me because I am enjoying the yellow color of my golden Ash at the same time and did not see the identical process happening in the rose leaves. I would love it if they could all drop right now but no such luck.