Rubus Breeding

I am spinning off a new thread from New Albino Blackberry - #44 by lordkiwi post.

Attention Rubus aficionado Are you into Raspberry, Blackberry and there relatives. Have you tried breading your own better berry. Do you have awesome wild berries. Come here post share your experience.

I have a particular set of crosses in mind and if I can obtain the source material I am going to try my hand at Rubus Breeding.

I’m going to start posting reference material as I discover it.

One of the first things I found is Rubus Cultivars is unlike apples which usually have 2 or 3 sets of chromosomes have far more polyloid levels 2 3 4 5 6 so with out lab tools and DNA analasys crosses are more likely at the same polyoid level. Fortunately found two studies that give the levels of a good number of species and cultivars.

HORTSCIENCE, VOL. 30(7), DECEMBER 1995 1447 HORTSCIENCE 30(7):1447–1452. 1995. Chromosome Numbers of Rubus Species at the National Clonal Germplasm Repository

Survey of Chromosome Numbers in Rubus (Rosaceae: Rosoideae) in the article viewer you can export it to PDF


The Burbank has some mean thorns and out of the few seedlings that sprouted they all where thorny. I’m not even growing them out if I see spines. I have too many other things going on to seek out different shades of thorny cultivars.

Dont throw away those seedling yet. Thornlessness can arise as both recessive and dominate gene. You may simply need to back gross with your thornless selection again for the genes to express there selves. Rubus Ulmifoius ‘Merton thornless’ is a recessive gene its not going to express its self with one crossing. ‘Austin’ on the other hand has a dominate thornless trait.

Sources: Why are Some Blackberries Thornless and some Thorny? | Mississippi Fruit and Nut Blog


I breed Rubus, and have a number of crosses going. On blackberries I’m still evaluating cultivars and such. The ploidy level is a problem, if I was younger I would work with different levels using chemicals to match levels. Being older now, experimenting would take too many years, of which I do not have. I will try with blackberries, but have low expectations. I’ll have a lot more to say come next spring as I have 4 or 5 crosses that should fruit, mostly raspberries. I have blackberries going too, and the crosses went well with what looks like good takes. Only time will tell, and I’ll know more next spring again, if the seeds germinate.
So I’m doing more with raspberries, but have blackberry crosses just done this year, I suspect some of the crosses are sterile, so I have low expectations. I will be doing more crosses next spring.


I’m going to try my hand in breeding next season. found a semi thornless wild blackberry id like to try and improve on. reading on it as much as i can. can anyone recommended a good book describing how to breed these species in depth? haven’t come across much on the net.

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I too will throw my hat into the ring and give breeding rubus a go
the two main cultivars i will be working on is a cross between “polar berry” aka nettletons creamy white and local NC thick cane blackberries.


a hybrid between a yellow raspberry “Anne” and a japanese wineberry to improve vigor and growability in the south.

I will be backcrossing and or inbreeding to achieve final results of a white blackberry with good flavor that can be grown reliably in the south and a yellow fruited wineberry that has good yield flavor and vigor

here is a link that should prove helpful to those interested in trying new crosses and i will inform you as the information was relayed to me that just because where someone has failed does not mean you will not succeed.


What techniques do you germinate your Rubus seeds? So far I have had no success. I have tried to start some seeds I purchased from eBay and they are still outside in there pots doing nothing. Pre-stratified I think just means old. I have started to research germination rubus and discovered that the difficulty ranges from hard to impossible. I am posting links to the articles and papers I have read so far.

At this point I plan to start yet another winter project. I am going to buy few thousand Rubus seeds from china and practice.
Germination Protocols

Drying Interferes with Germination of Blackberrys

Scarification and stratification protocols for raspberry

the TLDR synopsis; Acid Scarification with 95% sulfuric acid for up to 3 hours works best. Less time for thinner seed coatings longer then 3.5 hours cooks everything.

I use 30% sulfuric acid and had them germinate at 15 minutes. I may increase that to 20 minutes, but 3 hours seems way excessive.
It has been my experience that most Rubus seeds only last a short time. I store mine in the berry itself i.e. I don’t clean the fruit of seeds till I’m ready to start them. You can store Rubus long term by freezing, must be dry!

So most seeds you buy will be dead. The best way to practice is take some fresh brambles and remove seed, use those right away. If you don’t have any, go buy some fresh berries. Driscoll has about 20 raspberry cultivars you cannot buy, they developed them for their farms. I just saw about 10 new raspberry patents and 10 new blackberry patents by them. So growing out seed, might not produce mother plant, but may result in a very good berry from gene lines we cannot purchase.

That should be Scarification, they do need stratification too.

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3 hours seems way excessive.

I would agree, the 3 hour figure seems to derive from germinating seeds of wild selections, with much thicker seeds.

Driscoll has about 20 raspberry cultivars you cannot buy, they developed them for their farms. I just saw about 10 new raspberry patents and 10 new blackberry patents by them. So growing out seed, might not produce mother plant, but may result in a very good berry from gene lines we cannot purchase.

Very true, though Rubus is known to self clone in there seeds so there is a very good chance some would grow true. I have had some outstanding Driscoll berries and If I had unlimited space I would grow some out. But for now I am going to keep Driscoll genetics away from the things I am growing.

Well to some up what i meant it might be worth practicing with Driscoll as anything that germinates, might be worth keeping. I don’t know much about Driscoll, although I am a fan of Zaiger Genetics. The Pluots are awesome.
Also to point out bought seeds usually fail. Something to try after you got it down, so you know it’s the seeds. Blackberries have thicker coats and take longer. I still would not go 3 hours, maybe an hour with blackberries. I ran trials on raspberries and 15 minutes in 30% acid worked best for me. None came up at 30 minutes.

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I didn’t mean to imply it wasn’t or I was not going to try. I just dont plan to grow the plants out.

I dont think Driscoll is Monsanto or anything. But you can never be too sure

I read about some of the legal brutality in strawberry breeding.

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That does not surprise me at all. The way of the world. I would not describe it as legal brutality, the farmers had good reason, It didn’t even go to court. They worked it out.
I completely understand why those breeders left too. Generating billions of dollars in sales, yet they live on University paychecks. Others are reaping the benefit of their work. I would have left long ago.

Hi all! I’m a little late to the party, but I hope my two cents are worth something (and I’d love to take away a little something while I’m here).

Back when I thought most Rubus wouldn’t grow at home (Puerto Rico), I had gotten a Rubus probus off the local hillside and had planned on acquiring other tropical species to breed, like R. niveus and R. glaucus. I was hoping to make “Tropical” versions of Purple Rasberries, Loganberries and other such hybrids. But then I found that several cultivars of conventional Rubus would fruit just fine at home, so I redirected my efforts to them (I’ll come back to the tropical ones later). I acquired R. occidentalis “Black Hawk” and R. idaeus “Caroline” about four years ago. I’ll be honest, I’ve been neglectful with my plants. I take pains to ensure their survival, but I don’t usually give them ideal circumstances to thrive. Nevertheless, while I’ve yet to see a single R. occidentalis blossom ('cause I end up snipping the branches before it’s their time to flower), I’ve gotten several Red Raspberry crops so far. The advantage of primocane fruiters… But anyway, back to my efforts.

I took pollen from the pollen donor, dried the anthers in open jars, cut open Caroline’s flower buds and dabbed on the pollen with a brush, repeating the process daily to ensure a crop, while keeping the flowers isolated (first with plastic bags, then later by just snipping off competing flowers). I tried this three times between 2015 and 2016, but the flowers always ended up withering within a week. I put the experiment on hold, but I’ve repotted my plants to get some good growth for the next flowering season, to give it another go. I’ve wondered about using mentor pollination, but I’m not sure I need to go that far.

I am concerned with germination, so I may use the acid solution, but I was under the impression that germination is only an issue with dry seeds… Are the seeds troublesome when fresh off the fruit as well?

Yes, they have a coating that is dissolved by stomach acid (sulfuric acid). So yes, you have to treat them, or wait 2 years if planted. Raspberry seeds can go bad fast. I would say most sold are no good. Not all! If frozen after drying, they can be stored for years.

As far as your hybridizing it sounds like you’re doing everything right. If you’re using pollen from another species, that may be the issue, they are not comparable. If could be different ploidy levels, or other reasons. Even though blackberry-raspberry hybrids exist, making one would be difficult. You would need to do hundreds of attempts, and maybe get none. . Three exist, the loganberry, tayberry, and boysenberry. All other blackberries with raspberry genes, come from these three, some used all three, but no new crosses have been done. tayberry is the newest in 1979. Loganberry in 1881, and Boysen in the late 1920’s. Almost impossible to make a cross species cross. Their is also the wyeberry, but it seems to be a strain of boysenberry, except it’s bigger, it could be a 4th cross, or just a cultivar of boysenberry, maybe a sport or something like that? They taste the same, wyeberries are bigger., grow large canes. Their is no info on this berry.

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I used Fragaria vesca “Reine Des Vallees”. The idea was to replicate Luther Burbank’s attempted Strawberry-Raspberry hybrid ( Untitled Document ). He succeeded in getting several plants, but they were unproductive. My idea was that he probably used a diploid red raspberry with the octaploid garden strawberry. A diploid strawberry like F. vesca would have been a better match (both Fragaria and Rubus have a base chromosome count of 7, and together with Rosa and Duchesnea, they constitute the edible members of the Rosoideae subfamily). I’m not the only one who’s attempted this recently; a guy in Australia is actually growing out some hybrid plants himself. We’ve been sharing info on his own blog post: Mudflower: Strawberry Raspberry hybrids

Honestly, the idea is not too wild. If successful, the outcome would probably be Rubus-like. They seem to have a similar fruit structure: the main body of the strawberry fruit seems homologous to a Rubus fruit core, while the achenes seem homologous to the Rubus’ drupelets.


this thread is next-level stuff! interesting read, but I won’t be breeding bushes anytime soon, if ever, as i’m a bramble beginner, a rubus rube. i’ll be happy just to taste my first prime ark freedom.


I want to see the results of this very much.

My experience with seed is nothing sprouted in spring but did in late summer / fall . Then more this spring . So one must be patient .

I want to do some strawberry breeding too. Mostly my ideas are for things i would want, Like I like pineberries, but they are soft. i would love to develop a firm pineberry, that has shelf life, I could probably make a lot of money if I did. So probably won’t happen. I collected White D pineberry pollen, and waiting for my Archer strawberries to flower. The are firm aromatic, and very large.

It would probably look like a Framberry, which looks like a cross, but is pure strawberry. I grow these too.


I’m excited to try to make it happen, but I’m a little bummed that my first attempts failed. My guess is I shouldn’t have dried the pollen. Strawberry pollen is also heat sensitive, so that may have compounded the issue. Next time I’ll use fresh pollen, and I might also like to try the cross in reverse (strawberry seeds are much easier to sprout, and raspberry pollen is easier to harvest). If it works out, I’d like to try it with pale-fruited types, like F. vesca “Pineapple Crush” x R. idaeus “Anne”. Then there’s other diploid brambles, like R. occidentalis and R. ulmifolius.

Speaking of pale fruits, has anyone tried to breed a White Loganberry? It seems like the logical next step with white blackberries and yellow raspberries. Even black raspberries have yellow variants (“Yellow Purples” anyone?). I’m down to try it myself.

For the tropical hybrids, I have R. probus, I’d like to get R. rosifolius, R. niveus, R. glaucus, R. nubigenus (really a highland species) and R. macraei. The fruit size with R. nubigenus is insane! Rubus macraei is a special case, as there is a thornless purple-fruited liana variant that has the typical Hawaiian Rubus bitterness, and a thorny upright large-yellow-fruited variant that is sweet. The latter is the one I want, but I’ve no idea where to find it, and the original article states its location as a Koa forest on the windward slopes of Mauna Kea.

I was interested in crossing Fragaria vesca with F. moschata, but after reading about another man’s trials in crossing F. moschata with F. x ananassa ( Berried Treasure | Science | Smithsonian Magazine ), it seems more trouble than it’s worth. Both are exquisitely flavored, apparently, but the musk strawberry’s flavor profile is so chemically complex that it’ll probably get unbalanced in the vast majority of the hybrids produced. I’d like to get my hands on some F. x vescana, if they ever become available.

I plan on acquiring Rosa pomifera soon for another breeding experiment, but I might include it in this one too… But then, I’d need tetraploid brambles and strawberries to breed successfully. Are there any diploid fruiting roses?

For all the hybrids I try, I’d like to get my hands on Oryzalin (or failing that, Colchicine), as an added precaution in case they come out sterile. Does anyone here know where I might obtain that?

Also, that Framberry looks good! How does it compare with other strawberries? I think the actual hybrid might just look like a regular raspberry (with an altered flavor profile), as Burbank’s mule did produce some fairly normal-looking drupelets.

Also, check the Journal of Heredity (1920) Vol. 11, pages 194-203 for details on Rubus nubigenus ( The Journal of heredity : American Genetic Association : Free Download, Borrow, and Streaming : Internet Archive ), and the Journal of Heredity (1921) Vol 12, pages 146-150 for R. macraei ( The Journal of heredity : American Genetic Association : Free Download, Borrow, and Streaming : Internet Archive ). It’d be easier for me to just post the short pdfs I made of the two articles, but I’m too new to post any files.