Are rugosa hybrids usually self-infertile, that is, do they require pollen from another variety to form viable seed?
Specifically, are Rugelda and Fru Dagmar Hastrup self-infertile?
This question came up on another forum; I have no experience breeding rugosas.
Most diploid species are self-infertile and R.rugosa is no exception. While I have no experience with Fru Dagmar Hastrup or Rugelda, I do have four other Hybrid Rugosas and several R.rugosa plants. My experiance with them is that they will not set hips unless they have been pollinated from another source. They also seem to be fairly picky about what they accept also, as some of my crosses with tetraploid pollen did not take.
How self-infertile a Hybrid Rugosa is will depend on how much R.rugosa is in it. Fru Dagmar Hastrup looks pretty much like a straight R.rugosa clone with little or no other species or variety in it, so it probably is self-infertile.
The flowers and leaves of Rugelda on the other hand don’t look anything like a Rugosa, so probably has very little R.rugosa in it and has a quite a bit of other stuff in it. I would not be surprised if it was self fertile even if there is a good chance it is a triploid.
I can’t say about the good Fru, which I don’t have, but Rugelda (“Rugelda, Rugelda, let down your golden petals!”) sets OP seeds, so it’s probably self-fertile. There may be some varieties that are self-infertile, but I suspect that more are self-fertile. If you do not emasculate the seed parent and you use pollen from varieties that are sufficiently different from the wannabe mother plants, you’ll probably be able to tell which ones are from self-pollination.
I have a couple of batches of seed collected from Fru Dagmar Harstrup (Frau Dagmar Hartop). The mother plant, at the National Australian Rose Garden in Tasmania, had loads of hips but the bush was situated in the middle of over 5000 roses so the pollen could have come from anything. No germinants yet. I also have seed from OP Schneezwerg in that I’m hoping will germinate soon. My ‘Scabrosa’ set no hips last year despite being in the middle of over 100 different roses. It was it’s first year in the ground and didn’t flower until late summer when the other roses were resting. I intend to use it extensively as a seed parent this year. There are posts in the archives here that describe the self-incompatibility of R.rugosa. I’d like to try Roseraie de l’H
My Roseraie de L’Hay set an OP hip, I’m curious as to what it might produce.
I just collected OP seed from ‘Hansa’ which was surrounded by a wide variety of different roses. So- am I correct in assuming that 'Hansa ’ is diploid, self-infertile, and pollinated by the various roses about? Thanks for the info! Robyn
HMF quotes ‘Hansa’ as being diploid:
Yes, you would be safe to assume that Hansa is a diploid, self-infertile and was pollinated from the surrounding roses.
If nothing else is in bloom when my Hybrid Rugosas are, the hips turn brown and fall off. So if you have hips then they most likely were pollinated from whatever is growing near them.
Thanks Simon and Paul- I’m way more excited to see what comes from random pollination as opposed to self-pollinated Rugosas! Robyn
I agree that R. rugosa has poor self-fertility. When I was kid, we grew a small hedge of a R. rugosa clone that had been collected on a beach in Cape Cod. It is partially double, so it must be a fairly recent escape from cultivation. I remember that it would produce a few hips in some years. Later, when I grew the same clone in my garden with many other R. rugosa selections, it formed many more, MUCH larger hips. This particular clone gets a fair amount of blackspot, so I don
The situation with rugosas must be rather mixed. This spring I gathered hips from what appears to be R rugosa rubra growing on a bank overlooking a parking lot and between there and the road. All were planted by a commercial landscaping firm and I had assumed they are a single clone propagated and shipped in, given their uniformity of size and shape. No other rose grows visibly within a quarter mile, then only Knockout in some other landscapes.
This fall I went back and it appears that every flower from before July has 50 or more seeds in a ripe hip. The later ones are maturing now. It could be a case of heat overcoming self-infertility if that is actually a factor because we’re certainly warmer in KS than the Dakotas. But it wasn’t that hot through the spring season.
Perhaps this isn’t really Rrr, or perhaps they were propagated from multiple interfertile clones. Whatever it is (they are) it is a good rose for bloom, bush and berry.
I checked my seed trays this afternoon and I have four up from OP Frau Dagmar. There seems to be a bit of variability in these four but so far they look quite strong.