What is the easiest and hardest steps in rose breeding?

Recently, I’ve had the discussion with someone. They keep insisting I need to practice the pollination process, but I keep insisting that knowing roses thoroughly (lineage, general growth habit, differences in growth and characteristics based on climate and region, ease of use in breeding, among other time-consuming things) is the real heart of rose breeding. As a note, this person hasn’t done any of their own breeding before and hasn’t read anything from the RHA or other breeding resources.

Yes, I’ve heard that ultimately rose breeding has a lot to do with pure chance, but having a goal in mind and knowing which choices to make (and why) seems to be what makes most successful rose breeders successful. I believe I even heard Tom Carruth say in a lecture this is why Herbert Swim was able to create more successful offspring with less crosses than other breeders. He knew his roses intimately and planned based on that knowledge. Yes, the numbers of pollination do affect the genetic outcome, but knowing the roses in their program intimately, and knowing the ones they want to bring into to their program, seems like a much more difficult, time-consuming, and more important process than knowing how to pollinate.

I may be wrong, but I learned the actual pollination process within a few hours. Over a few weeks, I got better at it, but my actual skills for picking apart a flower and pollinating seemed to plateau quite quickly. Yes, I’m sure it’s possible to get better at it. It is absolutely possible to learn skills to make things faster and more efficient, but I don’t think emasculating and placing pollen on the stigma is that difficult when compared to other skills and knowledge necessary to successfully breed. It’s all important. All of this has it’s place, but the why of rose breeding (why you choose certain lines and cultivars) seems to be the thing to prioritize time-wise than the how of rose breeding (pollination).

Ultimately, I’m still a noob at this. What are your thoughts? Specifically on what is the easiest and more time-consuming or difficult parts of rose breeding.

Thank so much!

Actually, because I enjoy it, it’s all “fun”. What is the most time consuming and “difficult” is digging anthers out of an extremely double bloom. Handling moss rose blooms is also time consuming and “difficult” because the mossing tends to be sticky and the hard moss types can actually penetrate your skin.

Determining what your goals are and how to get there is time consuming, but also fun. There can be a lot of research involved, which can be time consuming, but is also fun. What I don’t find “fun” is writing out many of the same tag to mark pollinated flowers when I’m making a large number of the same cross. To me, that is boring. The part I find frustrating is killing off the snails and slugs to prevent them from eating my paper tags without the dogs eating the “pet safe” snail bait. ANYTHING “pet safe” or “organic” is a “dog treat” at my house, so nothing gets used unless it is safe around the “tiny tyrants”.

Those are definitely aspects I wouldn’t have initially thought of :lol: Trying to get anthers out of very petaled roses is definitely a pain!

I guess I’m simply trying to determine which aspects of rose breeding to focus on over the next few years. I guess what I’m trying to get at is which things take time from a learning-perspective. This person thinks I need to focus primarily on practicing pollination rather than getting to know rose lineages, growth habits, and individual uses for each cultivar. Yes, it’s important to be able to pollinate well so you don’t damage the flowers and never get hips! But if you don’t have a good understanding of roses, you could add years to your breeding program without much success. For example, this year, I made 100 crosses blindly. I got like 4 hips. If I would have known and followed which roses and lineages work well for breeding, I could’ve doubled or quadrupled that. At least, that’s what I’ve taken from what I’ve learned so far.

Pollination is not that hard. I’m lazy, so I just rip off the petals and stamens, unless I want their pollen. then I collect them in a plastic petri dish and pitch the petals. I use 25 or so colors of plastic tagging tape to represent pollen parents. I make a list to carry with me. tie the tape around the stem under the flower and your tagging is done. Can do a hundred an hour on something easy like Silver Moon which has few petals, easy stamens. Assuming I have pollen enough that day from an abundant donor such as Carefree Sunshine. End of season collect all the ones with same tag color from one mother and you’re ready to collect achenes. That can be the most tedious part with something like canina which gets very sticky hips when fully ripe. A dreadful mess to get them out. Some others are very tough and need a sharp knife to split and pick out achenes. For 25-50 or more hips, use a Waring blendor. Everything from there on is interesting because it is unknown and an adventure. Will it turn out as hoped, or mroe likely as expected.

Perhaps…a bad weather year can foul up all of your plans. A few of my most desired pollen parents provided more than enough pollen, yet due to a very cold spring and summer, VERY few of my seed parents provided any flowers until very late in the year. Late enough that I made probably less than 5% of the number of pollinations I have made over the past several years. Knowing how to generate hips and seeds is definitely necessary, but even before heading off to pollinate a bunch of blooms, I always advise planting all the self set seed you can find so you know HOW to germinate all those wonderful seeds you’re setting out to create. While you are learning lineages and determining what has the greatest potential for getting you where you want to go, plant seeds! See how raising them is going to work where you are and what you need to do to make it work best. Look up the roses you most admire and find out what made them. Look at what performs best where you are and see what made them. If at all possible, look around where you are and see what makes a good seed parent. What sets hips easily and by itself. Germinate THOSE while you’re studying. Make use of all of your time so you’re multitasking. But, remember, the best laid plans… and all. Few years are going to work the way you expect them to, so just roll with the punches and watch what works. You can learn everything there is listed for what made what and there is no guaranty they will even succeed where you are. So much of it is climate and variations within each climate. You simply have to arm yourself with all the knowledge you can, watch and let the roses teach you where you are and be prepared to dump it all when you find presumptions were made which didn’t pan out or conditions have changed sufficiently to trip up what you selected to work with. The roses will teach you. Just watch and listen.

Hardest initially will be just letting seedlings go that have some problem or accepting the number of weak seedlings that’ll die off from the modern classes (die off in species and older classes is much much much less for me). Letting seedlings and unproductive plants go is hard.

Next would be figuring out what you’re trying to achieve and how to get there. There’s just a lot of variety and areas to look at that “everything” isnt really an option.

Next would be realising other peoples experiences wont always reflect yours, whether its differences in climate, care, etc so if you want to try something, do it. ie Crested Moss is often stated to be near sterile. I still harvested 34 seeds from it a few days ago, hips ranging from 1 seed to 11 seed a hip.

Culling is the hardest thing. Stratification and growing of young seedlings is more difficult than pollination.

The analogy of making human children is apt. Pollination is easy and fun. You can get better at it with practice, but you don’t need much skill to succeed. Germination is more difficult. Selecting which children to kill and which to keep is emotionally difficult.

Just get started with some OP seed from a reblooming rose that you like. That way you grow into the breeder’s cycle of hope and disappointment, learning to balance optimism and realism. You never know, one of these seedlings might end up being the one that gives you the most fulfillment throughout your life. Life is short, and breeding takes place over time. Moving into the second generation, when you’re using your own seedlings to cross with each other and with named roses, is a rewarding later stage of one’s hybridizing practice. But it takes time to get there, so you have to get started. There will be plenty of time for thinking, observing, learning, and strategizing along the way. As long as you are able to cull so your growing space doesn’t get clogged up with inferior roses, there is no risk or detriment to getting started right now.

Perhaps it is my morbid sense of humor, but Joe, you cracked me up! (Wishing I could add smiling emoji here)

Cutting seedling is definitely hard! Even harder (for me) and what I am working on is learning which seedlings to keep and which to let go. Not just based upon their performance, but based upon usefulness for future breeding. I don’t have enough experience in general, or with these seedlings in particular, to know which will make a good parent, esp. seed parent. But also, which will pass on the desired genetics, when the whole batch have the potential of possessing them.

Also, which path to follow in order to get to your goal. (Assuming the goal has been narrowed down enough to set in a direction.) If there are multiple possible options, which is the most plausible? Another reason I have found this forum so useful! Certainly climate and odd seasons will effect us, but trying to use parents that won’t set seed or won’t germinate the seed set, is beyond frustrating, not to mention time wasted.
So thank you for all who share their successes and failures.

“Selecting which children to kill and which to keep is emotionally difficult.” Yup, I agree, Duane, Joe is a hoot!

I agree, initially it was difficult to cull seedlings, particularly if they might contain genes I was after, but wait until every square inch is crammed with the buggers. It becomes VERY easy to dump them. VERY easy! You can more easily train yourself how to by limiting your space. As long as there is space, seedlings are like clutter and bills…they expand to absorb all available resources. Keep increasing your space and you will continue increasing your number of seedlings. That also helps you become MUCH more demanding, though some consider this “discerning”. I’ve never been one to be all that patient with disease on seedlings. After choking on them long enough, I am not accepting of disease at all. It is VERY easy to dump them if they exhibit much disease outside of the season and/or conditions I expect to see the issue.

I think that the answer(s) will vary depending on location. In my zone 5 area, the summer season is short and wildlife are plentiful. The short summer season limits the time that the hips have to ripen (especially for roses that flower later). Also, we do not have the same amount of sunny days that some other areas get.

When I first started in the 70s, getting the seeds to germinate (in my zone 5 area) seemed to be the main problem.

After that was solved with digestive enzymes, keeping the young plants alive was a major problem - rabbits, deer, other critters. I had to go to individual ourside cages and /or to inside grow areas.

that was solved with digestive enzymes

Dr. Kuska, I know you told us before how you do it but I couldn’t dredge up any relevant posts just now. Would you please give us a synopsis on your digestive enzyme methodology?



Patience is the hardest part for me. I’m surprised nobody else said that. I can get into the zen of most of the other processes while reflecting on the potential outcomes, but waiting to see if any of my efforts came to fruition is rough. (Spoiler alert: They generally don’t.)

I’ve been dabbling in pollen for over decade, off and on, but consider myself a newbie too. Personally, I think that until one has germinated a good 1000 controlled crosses, they are a complete newbie. (I have about 800 seeds in the cooler now, but mostly OP’s, and the first of them only just germinated this weekend.)

I note that, after claiming mastery of pollination, you say you only got about 4% takes. I would speculate that the bees had much greater success. (They always make me feel like a loser.) You may find that different cultivars have different times for receptiveness. (I had a rose whose stigmas were only receptive well before the blooms would have normally opened.) Study them and look for signs of a sticky, glistening coating. That’s the stage at which they seem most receptive.

Experience is important. You will find hat your experiences in your climate with your roses will differ from others. At any rate, the reports you read about will, after all, be statistically fairly meaningless. (Who is to say how many failed attempts were undertaken with a given parent before achieving the great successful crosses we can read about?) I would guestimate that no more than 1:10,000 seedlings are market worthy. Most of us will draw our conclusions about prospective parents long before we approach such numbers with any one plant. If you were to read other’s experiences with, for instance, Carefree Beauty or Marthe Carron on this forum, you would feel pretty discouraged from using those lines, yet they have created some of the most phenomenal descendants in recent history, which are still holding their own in the marketplace.

One final comment on experience vs. study: A kid selecting a team for a pick-up game of football, given a choice between the physics nerd who knows everything about the trajectory of spinning oblong spheroids in space and the dumb jock who has been out throwing the ball will likely know which one is a more promising athlete. Hybridizing is as much an art as it is a science, and artists develop their craft by doing.

In view of the dice-roll that every genetics mixing creates, it would be interesting to have a study showing the extent to which greater knowledge contributes to the successful creation of good roses. I wonder, for instance, if 10 moderately experienced amateur hybridizers submitted 100 (controlled cross) hips each to be professionally grown and evaluated, and that were compared to same number from a professional breeding house, what would the actual comparative “success rates” of the two groups look like? Would it be as much as 5 fold? Would it differ more significantly? or hardly at all?

Generating your own crosses and raising the seedlings TEACHES you patience, Philip, just as Susan and Charlotte are teaching it to you! LOL!

Well, I dunno, Kim. In that department, I kinda think of myself as the teacher. :wink:
(I once joked to my wife that the real reason for the institution of marriage was so that women could learn to deal with children before having one whose welfare is actually dependent on such… I think she refers to me sometimes as her first child.)

Well, there IS “that”, but kids teach you patience, too. (I hope!)

Well, the kid just got out of bed sigh and appeared to ask me for something, so I asked her which of us taught the other more patience. Dunno if she understood the question, but she proudly declared she was teaching me.

I had read that a well-pollinated flower is unlikely to be pollinated again by some fly-by interloper. That’s wrong. And it has been known to be wrong since the 19th century. And the wrongness was reconfirmed repeatedly in the 20th.

Darwin commented that the low seed-set on crosses among the legumes was due to their need for repeated pollination. This was reconfirmed in the 20th century when researchers planted common beans carrying 4 distinct genetic markers. Every pod was found to contain seeds from 2 or more “fathers”.

Research on apples showed clearly that the second pollination yielded more seeds than the first. Somehow, a few of the seeds that should have resulted from the first pollination were displaced by others from the second. Spooky! And just to put a sharper pointed on all this, apple blossoms that had been deprived of their petals were still sought out by bees and pollinated.

There is another point that should be mentioned. Fruitfulness begets fertility. Brock (1954) succeeded in crossing pear x apple and raising the hybrids. The “trick” was to identify pears that could be induced (chemically) to bear parthenocarpic fruit. Only these varieties, treated with the appropriate hormone, produced hybrid seeds. Years ago I read a similar case involving a chicken egg inseminated with pheasant semen. Only an egg from a breed of chicken that naturally produced some parthenogenic eggs was able to make the hybrid.

Girdling is an old practice that increases the yield of fruit in seedless cultivars. It has also been used, along with binding, to make stubborn trees and shrubs more floriferous and fruitful. Scapes from the normally sterile ‘Pearl’ Narcissus, left where they fell, resulted in seeds. Even a completely sterile hybrid Crinum produced numerous seeds, though they lacked embryos.

If a hip is developing, it is more likely to continue developing when more pollen is added. A cross that might not take when done with “pure” pollen, might succeed if the hip has already been stimulated into growth by a more compatible pollination.

The old neo-mendelian notion that stray pollen can “spoil” a cross is rubbish, unless you are obsessed with counting the contrasting phenotypes. In practice, it is usually easy enough to distinguish seedlings from the different pollen parents. Pollinate a pink-flowered Polyantha by R. multiflora, for example, than add pollen from the darkest crimson HT you can find. I doubt there will be any spoilage or confusion.

Brock (1954) succeeded in crossing pear x apple and raising the hybrids.

Brock 1954 svp?

Screenshot (96).png
There is also this from the John Innes Institute about pear X apple hybrids. Pear-Apple Hybrids | Nature