It’s getting difficult to get hip set here in the south due to heat and uv radiation, so I’m trying a few things. Probably have been tried before, but couldn’t hurt to try.
Masking tape in a “n” shape over the stigmas, gives shade and increases humidity.
Using more pollen per attempt to increase my odds.
Placing large, open, water containers near the seed parent to create a humid, lower temperature (hopefully, haven’t measured yet) microclimate.
I’d like to try mixing ground up old pollen mixed with David’s sugar water, lightly sprayed on the stigmas to help the pollen do it’s thing. I’m chronically short of pollen though.
I’m not being very scientific about it, just trying different things. Good luck to you all.
In Spring 07 RHA Newsletter, Michelle suggested placing small zip lock bags (with corners cut out) over blooms after pollination; bags are removed two days later. “I acheived greater pollination success when I used the bags than when I did not. In addition, not only did I have greater hip set rates, but I acheived what I suspect is more extensive ovule fertilization resulting in higher seed count per hip.”
I’ve done some pollinations in the late afternoon, about 4-5 p.m., I haven’t noticed any difference. I’ll do more.
The zip lock bags probably are better at holding humidity than my masking tape covers, the tape is likely better at blocking uv radiation…so maybe zip lock bags with some masking tape on them…
How about a wall air conditioner and a long extension cord 
Ok, I went all out. I printed a bunch of pictures of beautiful roses (rose por*n) to encourage the little pollens to go for it, then I poured Margaritas around the seed parent to help get her in the mood, and finally, there is a cd player playing Barry White songs nearby. Oh yeah, I’m expecting an AARS winner out of that cross.
Charles, I think you’re sure to get fertility with that combination, but your methodology sounds a bit old school.
I’d probably kick it up a notch or two with some high definition LCD screens, several Mojitos and some Michael Buble?
Just a little update, I’m getting good hip set again, but my tinkerings didn’t make an obvious difference. The untinkered neighboring hips were just as likely to take with the same pollen. My high temperatures have dropped a few degrees to 89-90F, which I think is what makes a difference. As long as I’m under 93F I think I will be golden. Luckily for me, coastal central Florida rarely rises above that.
Charles, for me I’ve found certain seed parents set better under warm conditions than others. That’s how I’ve ended up with a jillion Lilac Charm descendants. Some roses are remarkably fertile and others remarkably hard to work with. You’ll save yourself a lot of headaches going with something easy, especially to start with.
Any place you can get fertility is a jumping off point in my opinion. Use what works for you and go from there.
Good advice as always Robert. Does Lilac Charm pass this trait down? I just got Riverbanks which is descended from LC, how does Riverbanks compare heat wise, or do you recommend picking up Lilac Charm.
I have several easy seed parents: Gemini, Old Blush, Spice, Livin Easy, Westerland. Always looking for more though. Several others would rank as good seed parents. I should have a lot of seed soon. I do check out some that have unknown fertility though, if I think they are interesting, but not enough to frustrate myself.
This is the last season I’ll use Lilac Charm. I’ve learned LC is prone to black spot. It was a good place to start but I have many other more disease resistant options now. I think LC is especially valuable for use in crosses with species as it accepts almost any pollen.
Lila Banks is susceptible to black spot but not as bad as Lilac Charm which I suspect tells me the influence of banksia helps with disease resistance.
I need more information regarding Riverbanks and blackspot. I suspect it’s moderately susceptible.
Let me know how Riverbanks fares for you there if you will. You’re likely the first to try Riverbanks in that type of climate.
Riverbanks is a remarkably fertile triploid. It will set hips under a broad range of conditions. It is seed fertile with both diploids and tetraploids and works well as pollen parent with diploids and tetraploids. Riverbanks carries yellow and should work well with some of the seed parents you’ve chosen.
Riverbanks needs long cool Spring weather to look it’s best but remains fertile under less favorable conditions and will sometimes give a propensity for smooth offspring.
Germination and vigor in offspring is generally good.
I wonder if aluminum foil in the shape of a thimble (can be formed by placing foil over the thumb) placed over the emasculated stigma and again over the stigma after pollination would help. The foil should be tight around the pedicel. Incoming short wave radiation is reflected and as a result the temperature beneath the foil may remain cooler than the ambient temp.
At any rate it might be worth a try.
All the very best.
I was under the impression that the entire plant registers heat as a whole and will shut down most processes after a certain temperature. So, if true, does it shut down sexual reproduction save for seed maturation?
Plants will “shut down most processes” at critical ambient temperatures. However at those indicdated above (which seem to approach critical), the foil may give the plant a better chance of setting hips and developing viable seeds.
This technique works well for lilies in similar temp. situations and may just work for roses.