Thornless Roses

I will start off by saying I don’t know much about thornless roses (besides firing up google).

However last year I found what appeared to be a thornless multiflora, and took some hips off it and germinated the seeds. So far, all the seedlings appear to also be thornless. However I know that thornless roses are supposed to be unstable. Enrique wrote a little about his in the stability of roses thread. So my question is, how long do I have to wait before I can tell whether or not these seedlings are truly thornless? Do multifloras tend to be more stable in thier thornlessness? Cause I really was not expecting 100% thornlessness.



I’m starting to think there aren’t really truly thornless roses in the sense that it’s 100 percent genetically prickle free.

Lynnie is supposedly thornless… but it’s quite thorny in my garden. However, I see that new canes are either thornless or thorny.

My Queen Elizabeth seedling used to be thorny, but now there is new growth that’s free of thorns.

So, who knows.

I believe this is has to be some sort of survival mechanism when a rose senses the cold. (Thorns usually came from unusually cold weather in CA in recent years.)

I thought about it hard, and I thought that this may have been a way for a rose to insulate itself. Leaves will catch on the roses thorns which would insulate it during the winter. The more insulation a rose can hold on around it’s canes, the more likely it will not die.

But then again,

R. blanda and its hybrids are thornless and very cold hardy roses… which throws a monkey wrench into that theory…


There are more different genes that could express same traits.

Perhaps thornlessness from a hybrid tea is diffrent than found in Basye’s Legacy.

Who knows.

The thorniest Multiflora I ever saw was growing in a bed of thornless Multifloras at the Burbank house, Santa Rosa, CA. I don’t know whether it was a sport or a seedling, but it was wicked prickly.

The basis for loss of prickles seems to be different in roses than in blackberries. In the latter case the trait seems to “mendelize”, whereas in roses it is not so simple – and can be “dominant” in some crosses.

For example, Basye pollinated the very prickly ‘Basye’s Amphidiploid’ by ‘Commander Gillette’. One of the seedlings was completely smooth and free of bristles. He selfed this one and raised 36 seedlings: “None had bristles! 29 were thornless with smooth midribs; three were thornless with rough midribs; three had a few thorns and smooth midribs; and one had a thorns and a rough midrib.”


Genetics of thorniness is surprising.

One can get all thorny seedlings from thornless parents.

And reversely thornless seedlings from the most thorny parents.

Thorns are positive features for wild roses as much as desease resistance or scents that help pollinators. That the later features may be lost is well known. My belief is that it is this way at least some thornless roses went. Through loosing hability to build thorns. In the wild it would be promptly grazed to death…

Over the last decennies relative thornlessness was a breeding goal for greenhouse grown florist roses. Because it is contributing to better cut flower quality. Actually most are rather to fully thornless and no one would longer grow as it was thirty years ago thorny roses such as i.e. Tropicana or Color Wonder.

Hmmmm. I think the different genes thing might be true. What gets me is the waxy appearance of the canes, they don’t have little prickles lurking anywhere. It was my understanding that many thornless roses had little prickles or occaisonal thorns. Maybe that waxiness protects it a little bit? I guess I’ll just have to see if this is something that it passes on where I know that it has been crossed and not selfed.

Whatever the class may be, I hope more are bred but I think they’d be great for healing type gardens where non-dangerous plants can only be grown.

I have some of my first seedlings now which double up on 77-361. I am noting reduced prickles. I’m going to put these with some of the smoother banksia hybrids and we’ll see what happens.

Golden Gardens breeds a good number of thornless offspring when paired with any of the thornless Basye derivatives. Try Moore’s ‘My Stars’.


I’ve been working with a Sister seedling to ‘My Stars’ for a few years now. See “Lyn Griffith”. I’m hoping ‘Dornroschen’ will give it a bit of an edge in hardiness.

Golden Gardens, Joycie, Cal Poly, Work of Art, they’re practically interchangeable.

Amber, In the Extension Office Demonstration Gardens here in Abilene, Texas, We have Basye’s Blueberry and Mrs. Dudley Cross and both are thornless. Sincerely, Fred