Which plants are you trying to preserve? I played around years ago with glycerin treatment and decided that in most cases just using fresh Juniper, Balsam Fir, Cedar, Pine, English Ivy, etc. was easier for Christmas wreaths/decorating and could be tossed before they started looking bad.

I also remember trying these: Magnolia grandifolia leaves turned splotchy-looking. Nandina lost its leaves. Podocarpus, Cephalotaxus, and Pittosporum seemed too hard-leaved to take up the glycerin. Leucothoe, Cleyera and Pieris seemed to do okay, but to be honest I tossed them. These all do well in plain water for weeks, sometimes rooting (except Magnolia and Nandina). So instead of wreaths I used them in large table or floor vases with water, tucking in berried branches for color.

I think like you I probably tried in the Fall...maybe my experiments would have had better results in spring or summer. I also think I used branches too long...most over a foot long (I like big arrangements). I'm attaching a link which, if you scroll way down, has directions.

Hope others chime in here...I honestly feel I'm discouraging rather than encouraging and don't mean to, but I remember well my own disappointment. Luckily I then had a huge garden with lots of evergreens...wish I could have preserved some of it with this process to use now...Smile. josh

Here is a link that might be useful: Preserving Plants

Found another site in my files, with List 3 giving suggestions for which foliage does best. Also wanted to mention that most books call for hot water to be used with the glycerin, and solution to be stirred well before adding plants.

Also remembered that just for fun I had tried some Cyperus papyrus stems about 4 feet tall and they absorbed glycerine well but turned khaki color and drooped a bit. They dry naturally a pale tan so no improvement there...smile. Also Aucuba japonica turned deep black...rather striking actually. Probably tried others...for a few weeks I remember a walkin shower stall full of bottles with plants~~smile. Fun memories even if it didn't succeed. josh

Here is a link that might be useful: Preserving Plants

Thank you, Josh, for your reply. Your posts are always a treat-informative & exuberant. At last year's craft fairs, people wanted Christmas-themed dried wreaths, swags, etc.,so I thought I'd try to preserve some cedar to mix in with love-lies-bleeding and other red-burgundy drieds.
If you buy preserved evergreens, they're pricey, especially with higher shipping, and most are dyed hideous colors that don't exist in nature. I did have some cedar that 'took' last year, but I didn't add dye, and the color is a drab khaki-olive. It still has the wonderful smell, though. About 50% of the English Ivy worked.
While most info says to use 2 parts water to 1 pt. glyerin,
one grower said a 1 to 1 ratio worked for her. I'll try that next. There's also some variance in the post-harvest treatment-some sources say to condition them in water first, others say to put them in the solution right away, which is what I did. If I find a successful method, I'll post it. Thanks again!

One thought: At the risk of discouraging you further (smile), have you tried storing your glycerin-preserved greens with dried flowers attached? One of my books advised against sealing glycerine-treated items in air-tight container because of possibly developing mildew from retained moisture, and suggested hole-punched cardboard boxes instead. And most books suggest dried flowers be stored in airtight boxes with perhaps a little silica-gel added to guard against moisture. Just wondered how you had dealt with storage.
(I've erased this once because I do seem to be discouraging...but since you were nice enough not to mind my running on, I decided to leave it in...smile).

Hope your further experiments are successful. Although I decided I'd miss the scent of fresh-cut greens at Christmas, even if my experiments had gone well, it still would be nice to have some bits of greenery preserved for use at other times.

And that reminds me. (I just checked and I do still have an unopened bottle plus one "used". Did you know the glycerine can be strained and bottled for reuse? It does sometimes develop a bit of mold while using...but doesn't affect it and strainer removes it. Also that you need to add water to the solution while your greens are soaking as the water level drops?

Good luck...let us know how it goes. I'm tempted to try again with a few houseplants...maybe Dracaena or Cordyline leaves?~~smile~~ josh