I have started roses from seed for the past 3 winters. I gather the hips as soon as they are fully ripe. I take the seed from the hips and plant them immediately. I have had good luck with some and not so good luck with others. I got 40+ plants from seed from one rose last winter. There have been a couple of dozen of the seedlings that have bloomed a couple of times already. I pot them up when they start to bloom. The ones that did not bloom, I tossed. The mother plant of these seedlings is Summer Wind which is a single bright orange. The seedlings range from solid white single to orange double. Seems no two are exactly alike. The rose seed seem to germinate in cool weather. I have never had one to germinate when the weather was hot. I have also had seed to germinate and bloom within a couple of months from 4th of July, Golden showers and some unknown that I did not label. Lots of fun. Go for it....