Kim, back when I didn’t stratify I noticed that some years germination would be better than others. I also noticed that certain seed parents germinate better w/out stratification than others. This is in fact one of the reasons I came to use certain seed parents, ‘Sweet Afton’, Country Dancer’, ‘Armada’ among others. I doubt stratification prevents germination. Germination rates are better than ever with stratification. Of course I live in an extreme climate.
The heat here prevents me from hybridizing much of the year regardless. For me it’s easiest just to do it all at once. It IS tempting to hybridize in the Winter here. In fact I’ve been moving small amounts of pollen here and there.
One of the reasons Ralph was so successful is that the San Joaquin Valley accumulates quite a few natural chill hours, more than enough for most seed parents.
Kim,
I enjoyed reading what you just wrote. You and Robert both seem to agree in principle that omitting cold stratification as a strategy for selecting heat-loving seedlings is not unachievable.
You know, having just dismissed the whole idea for myself for reasons given above, I come back to the lazy thought of it being just a whole lot easier not to stratify as another primary motivator of mine, here…LOL
So, maybe, just maybe, I might give the ‘no-cold-stratification’ idea a shot just for this, my first season.
Thanks George. I honestly believe that most areas are going to accumulate sufficient chill hours, unless you live somewhere in Florida or somewhere similar. Robert is in the extreme low California desert. I’ve bred the majority of mine in the mid California desert. I’m now in the Coastal Range mountains, with elements of inland valleys with mild coastal influence. There are still enough chill hours for many of the lower chill requirement stone fruits and, so far, the species I grow. The seed I’ve planted were created in this coastal mountain environment and they are germinating well. This hasn’t even been a hard winter, so I believe I can save the time and effort.
Kim,
Here we get fewer chill hours than you describe in your winter, but hey, that’s ok too! LOL
Actually, selecting for heat-loving roses ONLY, is a must for just about all major cities on this continent. Cold-hardiness is a trait we probably need to weed out here, for better performance, but this is just my own speculation.
:0)
It’s counter intuitive but heat and cold tolerance often go together. Some of the most tender roses are poor doers in hot climates. For instance most Clark roses and Teas are not happy here most of the year. It’s too hot, not humid enough. Most Buck roses bred for cold Winters do surprisingly well.
Things are not always as one would expect. You’ll note Viru who has been hybridizing warm climate cultivars for some time often integrates hardy Shrub roses into his work.
I’ve often thought this Robert! When you drive around country Australia, including here in Tasmania, one of our more serious weed species is Rosa rubinginosa, which is from Europe and Western Asia, yet it is a problem here right up into semi-tropical Queensland:
This is one of the reasons I want to use it in hybridising because despite it’s more cooler origins it seems to have quite a wide temperature tolerance range.
Image ref:
Link: www.weeds.org.au/cgi-bin/weedident.cgi?tpl=plant.tpl&ibra=all&card=S24
Robert,
I agree.
I would never consider not using the entire gammet of roses as the PARENTS, it is the resulting cold-hardy SEEDLINGS of those crosses I want to weed out, be they progeny from cold hardy or warm climate roses, or whatever mix.
I was speculating that by omitting the cold stratification, this could be helpful in achieving this goal… just speculating, that’s all…
:0)
“this could be helpful in achieving this goal… just speculating, that’s all”
Somewhere in the archives of this forum I made the same speculation several years ago. You’re not the first to make this observation. However there’s nothing wrong with a rose being cold hardy as long as it meets your other requirements. Creating a rose with broad climactic tolerance is always a good thing.
Unfortunately breeding roses is as much as anything else a numbers game. The more seedlings you have, the more you have to choose from. Hybridizing is a bit like tossing the dice in hope that all the qualities you want will come together at once. This is especially difficult when integrating new species. One has to throw the dice with multiple generations.
The further one gets from the modern rose genome the more generations and tosses one has to make to achieve a product most people would want to grow.
Breeding modern roses together is very easy by comparison.
It’s still a crap shoot but a much safer bet.
As long as the “game” remains a fun game all is ok. :0)
“Safer” = Less expensive than dice.