Everyone here know I am new here. So this is a question for all. I have planted 10 new roses(our winter Aus), they are growing along a great rates in our spring, can I “try” crossing/hybridizing with them this year, Regards David.
This might be a trial and error situation. Some roses want to become well established before reliably setting hips, others will set fruit with their first seedling bloom, at 6-8 weeks. Some may tend to abort what looks like successful crosses, and others will set as many hips as you do crosses and add a few OP’s to boot. Fertility, health, establishment, vigor, and sometimes the weather all have a bearing on the outcome. Good Luck!
I don’t think trying would hurt them in anyway. Probably the worst thing that could happen is they won’t work.
With new roses I would recommend doing more crosses than you think you could handle if the seed does set. It seems like if they do set most new roses will drop most of their hips.