This real-time WEC run is “pushing the limits” in various ways.
Firstly, the size of the R.multiflora achenes and seeds within is soooo tiny, it is almost ridiculous to consider extracting them, yet it can be done with the box cutter knife.
Secondly, these R.multiflora hips are not showing any red color yet, but some do have patches of bronze, so I took a punt that some may have ripe enough embryos for the WEC to work.
These R.multiflora hips were supplied by my preferred local rose grower at Dural (north-western outskirts of Sydney). They were the best she could give this time of the warm season, so I took 'em hoping some might just be ripe enough to get a few seedling rootstocks going, fast!
Here are the hips I decided might be just ripe enough/ok for this WEC run:
Here are the contents:
Unlike the above photograph seems to show, most of these achenes looked too green (in good lighting) to be considered mature, but I chose a few that seemed to have a harder/whiter surface, and extracted their seeds.
Here are those seeds (the one second from the left is an embryo that escaped out of a slit in its papery testa!!):
It is just past 4pm here, so I’ll soak these overnight in tap water, and remove the testa tomorrow and then show pix!
It is 3pm the following day, here are the R.multiflora embryos soon after having their papery coverings removed a few minutes ago (they all slipped out easily, a good early sign of embryo viability in my experience):
One had a slightly less pearly appearance compared to the rest, but I am going to keep it, as it was not exactly waxy or discolored (such things often predict embryos doomed to fail IME).
I have left them all to soak at room temperature in tap water for three days, or less if any one of them decide to mould (drown).
Local weather forecast is: 73F - 90 F, relative humidity ~75%
To me it feels more like 100F right now LOL!!
Here are the 7 R.multiflora embryos, after having soaked in tap water for three days (none moulded):
Here is a polystyrene coffee cup, with toothpicks added as markers for each embryo about to be sown (one embryo per toothpick)…I poked holes in the base of the cup:
I picked one embryo with a spare toothpick, then removed one toothpick marker and placed the embryo in that spot. I then repeated this sequence, until all embryos were sown, and no toothpicks remained.
Because these cups are very easy to deform, I did not secure the cling wrap with elastic bands, because this might casue too much cup movement and risk embryos being displaced every which way. Here is the finished set up… the cups are sitting in a tray with water in it, for continual moisture supply from below:
I hope this method works, I prefer it if it works out ok!
I tried your technic with some modificaton (minor) and I have gotten germination for the first time of (Rosa blanda X R. woodsii) X Hansa. A similar cross gave plants that were over 8ft tall but were not hardy thus the injection of R. woodsii genes. I am hoping with a few more crosses for a hardy reblooming pillar. Special thanks to Margit.
That is fantastic, congratulations!!!