Desirai, there is a thing called a float test but to be honest I don't think it's all that accurate. Yo ujusst put them in a bowl of water and supposedly any that float are not viable, those that sink are. But in my experience that doesn't always work so I just use them all.

There are tons of threads on here that explain how to get them to germinate. Just do a search. But most rose seeds need a cold stratification before they will germinate. Put the cleaned seeds in a damp paper towel inside a plastic baggy and put them in the refrigerator for about 6 to 8 weeks. Then you can sow them in cups or trays and see if they will germinate.

If these seeds have been on the plant all winter, does that count as cold stratifying? or do I still need to do like what you said?

I just collected these seeds a few days ago off the roses in my yard ... :)

So this year I separated my seeds into 3 categories, those that floated, those that sank, and those that sank, and I sanded lightly.
Not a single one from the floater category sprouted. I had 2-3x more seeds in the sinker category than the sanded category, but both produced about the same amount of sprouts.
So I concluded that sanded sinkers do the best. Of course, most of my seeds came from the same plant, so YMMV.

Sanding ....... ?

Do you mean you put it in sand or you nicked it with sandpaper? :)

This post was edited by Desirai on Thu, Mar 20, 14 at 14:25

I sanded them with sandpaper. After the hydrogen peroxide/water bath, and before stratifying in the fridge.

I just put them in water and only 2 sank. The others are floating.

So that means that 2 are viable?

If you only have 5, I'd just plant them all. I had hundreds.

The sink test is generally pretty good. In the journals you'll see mixes of water and alchohol to make a slightly less dense mix so that more of the borderline ones sink. You'd do that for seeds that have viable floaters. Other mixes make water denser if you have a species that is non-viable sinkers.

Protocols often specify a preliminary soak before sorting.

Stratification: Most seeds need moist stratification, and the important temperatures are from about 30 F to 40 F. Warmer than that is is too warm, colder than that, and the chemical reactions are frozen into immobility. That's why 30 to 120 days in the fridge often work as well as all winter outside.