Were they hybrid varieties to begin with? If so then what you will get from their seeds normally will be two to four (on average) different types depending on their parental lines. That is assuming only two parents. If they were older open-pollinated (heirloom) varieties then their seeds will usually breed true.

And since you cross-pollinated them the variables increase to 16-20 if hybrids. So you will need to grow out most of the seeds, select the ones with the characteristics you want to keep, grow them out, select again, etc.

Normally it takes 6-7 generations of selecting and growing out to stabilize a cross-pollinated hybrid variety.

Dave

I cross-pollinated a cecile brunner to a ballerina. If I like one of the roses that came out, can't I just propagate by cutting?

When you say "select the ones with the characteristics you want to keep, grow them out, select again, etc.", do you mean self-pollinate the second and subsequent generations?

Do you have any suggestion for me to read up on hybridizing? Thanks, Dave.

If your first cross got you a rose you like, you can quit making crosses and propagate from cuttings from here on. Not much chance of that happening, but better than the lottery. Al

Keeping my fingers crossed.

Also, if the rose hip has 4 seeds, will all four roses be the same or they could be all different?

It is a function of the parental lines - i.e. the prior hybridization, polination, etc. I am unaware of the lines for cecile brunner and ballerina, but your seeds could be any of the roses used in the hybridizations upstream from your cross. Not likely that all 4 will be the same though it is possible.