Soft wood cuttings work best when taken from a cane that has just finished flowering. That's when the rose usually goes into growth mode again so it should be ready to sprout roots too. I take my cuttings in the spring right after the first flush has finished. For me that's the end of June and that way they have all the rest of summer to root and grow before they have to make it through a harsh winter. I don't recommend bringing roses inside for winter because they just don't like the conditions in most homes and, for me, will die before I can get them back out in the spring.

I don't know anything about the dog rose but if it's a species/wild rose I think they are usually pretty easy to root. Many of them will send up suckers on their own and those can often just be dug up and planted to make a new bush.

I've also seen people plant cuttings both in fall and earliest spring, sheltered under a mason jar in semi-shade, and just allow them to naturally root in the earth.
Springtime should show growth if the cutting rooted.

Thank you so much guys for the useful guides.
Seil, how long does it take to root for the cuttings you mentioned?
I have another question , if you don't mind .
I prune my roses heavily every year in late winter or early spring. How should I root the obtained trimmings as cuttings? Is the method similar to the softwood cutting? And will the success rate of hardwood cuttings be less or more than softwoods?
Thank you again

It can depend a lot on the variety of rose but it usually takes 4 to 6 weeks for me to see roots in the cups. My method is posted several times on this forum so I'm sure you can do a search and find it.

I can't say if prunings from dormant roses will take or not. I've never tried it. But I don't think the softwood method would work as well as the hardwood for a dormant cutting. I don't do hardwood cuttings but if you are looking for a method do a search for Roseseek's burrito method. It works very well.

As to which method is more successful, I think that depends on the rose variety. Some roses root quickly and easily and others won't root at all. As for which are which I couldn't tell you.

Thank you very much for sharing this valuable information.
What about semi-softwood cuttings taken in early fall ?
Does it works good? If so what conditions should the cuttings be kept in? Can I keep the covered cuttings outside in freezing temperatures (because I want to propagate a big number)?
Is it good to brush the cuttings' end with powdered fungicide or irritate the planted cuttings with diluted liquid fungicide once to prevent rotting?

Fall cuttings would have to be taken inside for winter. Keeping roses indoors is very difficult. The conditions are never right and most roses will die before you can get them back outside in the spring. There is a method where you stick the cane right into the ground and wait for it to root next spring but I don't know much about it or how successful it is.

I never use any fungicide on any of mine. As far as I know fungicide will not prevent rot. You want to use some type rooting hormone instead. The key to rooting cuttings is to keep the soil moist/damp but not wet and keep the humidity up around the plant. If the soil is too wet the part under the soil will rot. If the air around the top plant part is too dry the cane will dry out and die.

Thans a lot Seil for answering my questions