Hi! Does anyone know if Geranium x oxonianum crosses with Geranium sanguineum? The leaves and flower shape are more like the G. oxonianum seed parent but the deeper rose color makes me wonder about DNA from the G. sanguineum 'John Elsley' which is adjacent to the G. x oxonianum in my garden. I am posting photos of two blooms and a closeup of leaves (which do not resemble a leaf of G. sanguineum).

It looks like the bloom and leaf of Geranium x oxonianum which is itself a hybrid cross between G. endressii and G. versicolor. We have a few pink ones listed in the database:

French Crane's-bill (Geranium 'Wargrave Pink')
Hardy Geranium (Geranium 'Claridge Druce')
Cranesbill (Geranium 'Pat Smallacombe')

There are probably many with that deep pink shade; check out a few on this page for comparison: http://www.plantpref.co.uk/x-o...

My thought is that hardy geraniums will cross pollinate but the resulting cross may be sterile. That may be a good reason to try it. I have no scientific evidence to back up my thought. Just a thought.

Oops ... and I forgot to say that I don't know a thing about hybridization!

Thank you. I agree that there are bright G. oxonianum cultivars available as you kindly referenced. The parent cultivar in my garden has light pink flowers, so that is why I wondered if it self-pollinated, would it have produced darker, brighter flowered offspring? I am still curious about potential crosses of G. sanguineum and G. x oxonianum so I may experiment with planned crosses. The patented cultivar G. 'Blushing Turtle' is possibly a cross of these two species or "an unnamed selection of Geranium asphodeloides (male parent)"

Paintedtrillium said:Hi! Does anyone know if Geranium x oxonianum crosses with Geranium sanguineum? The leaves and flower shape are more like the G. oxonianum seed parent but the deeper rose color makes me wonder about DNA from the G. sanguineum 'John Elsley' which is adjacent to the G. x oxonianum in my garden. I am posting photos of two blooms and a closeup of leaves (which do not resemble a leaf of G. sanguineum).

• Hardy Geranium (Geranium 'Oxonianum')
• Uploaded by Paintedtrillium

The last photo shows G. sanguineum 'John Elsley' (Wayside Gardens introduction) which I thought may be the other parent for my seedling. Note the similar color and flower shape to my seedling. Currently available at https://www.forestfarm.com/ger... .

Can G. oxonianum cross with G. sanguineum?

In her 2005 book "Hardy Geraniums", Brigitte Husted Bendtsen reveals that Geranium sanguineum has 3 times the typical number of chromosomes making it less likely to cross with other species! "Geranium versicolor and G. endressii will, when planted close to each other, have many "children" together. It is questionable whether it is possible to purchase pure species of these two geraniums. In any case, it is pretty certainly an oxonianum geranium that hides behind the name G. endressii at nurseries. Geranium sanguineum, the bloody cranesbill, on the other hand, almost never crosses with other species. This is because G. sanguineum has 84 chromosomes, whereas the majority of other geraniums have 28."
ISBN-13:9780881927160, Publisher:Timber Press, Incorporated

Besides how closely related the three species are (sanguineum, versicolor, endressii) within the genus and their overall compatibility, matching chromosome numbers is the next big hurdle to overcome. In general, more success (if any) is had by using the higher numbered chromosome plant as the pollen contributor and the lower chromosome number plant as the parent that will produce the seed.

As I would with any difficult cross, if I were to attempt it, the cross would be highly controlled, so I would know for sure that any seed produced is actually what I want:
-- protect the subject flower from unwanted pollenations, i. e. from insects, by enclosing the flower in an organza bag or similar. This begins the day before the bud opens.
-- remove stamens from the subject flower before the pollen is ripe to prevent self pollenation - this will likely be just as the bud begins to unfold. Carefully peeling back petals or removing them altogether does hurt anything.
-- one to three days after the flower opens fully (watch a same age flower on the same plant), hand pollenate with the desired pollen.
-- immediately reclose the organza bag to continue to prevent unwanted pollenations.
--leave the bag on until the seed is ripe to catch the seed. Most geranium seed pods eject their seed with force, and you will never find them otherwise.

It is likely that if any seed is produced, zero to only a few would be actually viable and have the ability to grow into a plant. And then, of course, would they be runts or a beautiful hybrid worth keeping? Only time will tell.

Leftwood said:Besides how closely related the three species are (sanguineum, versicolor, endressii) within the genus and their overall compatibility, matching chromosome numbers is the next big hurdle to overcome. In general, more success (if any) is had by using the higher numbered chromosome plant as the pollen contributor and the lower chromosome number plant as the parent that will produce the seed.

As I would with any difficult cross, if I were to attempt it, the cross would be highly controlled, so I would know for sure that any seed produced is actually what I want:
-- protect the subject flower from unwanted pollenations, i. e. from insects, by enclosing the flower in an organza bag or similar. This begins the day before the bud opens.
-- remove stamens from the subject flower before the pollen is ripe to prevent self pollenation - this will likely be just as the bud begins to unfold. Carefully peeling back petals or removing them altogether does hurt anything.
-- one to three days after the flower opens fully (watch a same age flower on the same plant), hand pollenate with the desired pollen.
-- immediately reclose the organza bag to continue to prevent unwanted pollenations.
--leave the bag on until the seed is ripe to catch the seed. Most geranium seed pods eject their seed with force, and you will never find them otherwise.

It is likely that if any seed is produced, zero to only a few would be actually viable and have the ability to grow into a plant. And then, of course, would they be runts or a beautiful hybrid worth keeping? Only time will tell.

Thank you so much for your helpful recommendations!