Basically, the germination clock doesn’t run while achenes are in the hips, but the final germination % goes down<<<<<<<<<<<<<<<<<<<<<<<
That is real interesting Larry, thank you!! I am really looking forward to reading your article!!!
I agree with Larry about the germination clock not starting until the seeds are removed from the hips, but I don’t necessarily agree with the decline of germination rates if seeds are left in the hips for longer times. I haven’t seen any evidence of that in any of the experiments I did years ago.
I harvest seed starting in October and finish collecting the last in late November, opting to allow each plant to mature hips according to its own ripening agenda. (Pollinations done out in the open garden in July obviously mean later harvest dates than pollinations done under plastic in early May) All hips are collected in a Tupperware style storage bin and left at room temperature in a small room off the kitchen. Temps there run between 55F and 70F, which is what I think of as the “warm” portion of the stratification process. By the first week of December, all hips are moved into the fridge (after cataloging in a spreadsheet) where they remain until late January/early February. Then, I start cleaning the seeds from hips and returning them to Ziploc bags with damp paper towels for the remainder of the chill period. (Late Feb or early March) Seeds are allowed to get as moldy as they want. I proved to myself years ago how germination rates were affected by the presence of molds: in almost all cases, germination rates went up dramatically if molds were permitted to digest the outer achene. Sure, sometimes you can get a mold form that will damage seeds rather than assist, but it doesn’t happen often enough to deter me from continuing the process as I do.
So, why leave the seeds in their hips for so long? One of the varieties I have used for years is Moore’s ‘Condoleezza’. When you clean its seeds, you can be guaranteed that they will start to germinate within a couple weeks of cleaning. Since I do not like transplanting germinated seeds direct from fridge-to-pots (I always get a lot of seedling deaths doing this), then I do whatever I can to deter “in fridge” germinations. That means leaving them in the hips until February, so that the time elapsed between cleaning and sowing is no more than 3 to 5 weeks. I try to clean the fast germinators last, so I can hopefully avoid any germination before sowing day.
It works for me, but not necessarily recommended for everyone; determine what works for you, in your situation.
Paul said,
“Temps there run between 55F and 70F, which is what I think of as the “warm” portion of the stratification process”
Cleaned seed is kept outside here, where analogous temps regularly run over 100 degrees during a similar, in my case, hot, stratification period.
It makes sense that Paul doesn’t get early germination as he waits to remove seed from the hips till later in the process.
I usually have a proportion of each seasons crosses germinating by December.
Just for fun posting a photo of a group of seedlings taken this morning. This cross was made in April of this year.
If I’d any idea the germination rate would have been this high I would have sown the seed much more sparingly.
This is a 4" pot sitting inside of a 1 gallon container.
argh… stop trying to tempt me into planting, Robert! I normally plant on Boxing Day, but I have decided to wait an extra month this year as things got a wee bit tight in the house last year before I could moved a batch of pots out to the cold frame.
Seeds are all cleaned and have been in the fridge for about a month to 6-weeks, before that the hips were in the garage. I’m still at the stage of trying to figure out what works the best for me.
Don’t do it Liz!
We’re at almost record breaking temps here today with highs in the 80’s. It’s 64 degrees out there right now.
I’ve been running around with shorts and no shirt in the afternoon.
It’s supposed to cool down to the high 60’s low 70’s here next week. Of course the roses love it.
At this rate I could have buds forming by new year.
It’s taken me several years to work out what works best for me. Now I honestly think I could hybridize year round if I had the space and time.
Very few people have ever tried hybridizing in a climate like mine, but it works just fine once the logistics are sorted out.
We all have to work out for ourselves what best suits our climate and situation.
I started half of the Rosa glutinosa’s yesterday. I figure I’ll plant a hedge in the gutters … 
If theyre anything like Rosa rubiginosa and Rosa canina, they’ll have a 90% germination ratio. When I get hybrid seed from Rosa pomifera in about 2 years, I’ll let ya all know how well those germinate too.
The first “Christmas Baby”, a Hall of Flowers X DLFED 2 seedling. Kind of getting off to a slow start, but they were only sewn on Thanksgiving. Kim
Germination starting here, including a duchess de montebello grandchild. Germination here usually peaks in mid february.
Kim… What do u use for germinating soil?
Well, since I germinate outdoors in an area which can get rather hot and dry, I use Miracle Grow Moisture Control potting soil in raised wooden boxes on saw horses. They are covered by make shift lids with hardware cloth stapled to them to keep the thieving varmints out. Unless the rain drips off the root continuously, it doesn’t remain too wet and it prevents the seedlings from completely drying out between waterings. I know it would be too soggy indoors or in cold, wet areas, but I am on the cusp of the SoCal coastal mountains where they meld into the first hotter inland valley. I get some coastal fog, humidity and a healthy dose of valley heat. I’ve used the MG for several years for everything and love it. Nothing else remains wet enough when the winds blow or the heat hits, and it can hit virtually over night.
We’ve just had about the rainiest period I can remember in many years and now the wind is beginning and it’s dry. A very perverse climate…rain like the devil and flood, followed by near zero humidity and winds to desiccate everything that nearly drowned a few days before.
Thanks Kim… Looks like you have a real good start
You’re welcome Larry, thanks! I’d feel a whole lot more secure if they were springing up like last year. We’ve had nearly our annual rainfall in less than two weeks and only one is peeking out so far. Murphy will probably interfere this year. Instead of just tossing them in rows, I put each of the “valuable” seed in a peat pellet to make transplanting easier and to keep better track of them. I didn’t end with as many as last year and planted primarily those I really cared about, passing along most of the selfs to others who wanted to try their hands at raising seedlings. They’ll probably have tremendous success and I’ll have two tables full of spent peat pellets! LOL!
All my usual sources for the pellets dried up this year. I can find them in one and two dozen boxes at the HI stores for several dollars, but I like digging them out of the bulk boxes for a dime or less, each. Looks as though I will have to buy them in bulk on line. Kim
Kim