Rose insect pest control
This year has been the worst for my roses ever. Many (not all) have suffered from some sort of leaf pest that appears to eat away the green of the leaves, leaving them brown, lacy, skeletonized. (One problem is, I can't actually find any insects, larvae, etc after searching the plant).
After consulting a few rose people it seems the problem is either some kind of tiny inchworm/caterpillar or sawfly larvae. Maybe they've finished their life cycle for now so I'm not seeing them. In any case, I need to develop an organic rose program so I'm here for advice.
So far, my efforts at rose growing have been the same as the rest of my garden, which is mostly perennials: add a lot of compost at planting time, then nothing else. This has worked great for perennials but apparently I could be doing more for my roses.
Here's what has been suggested:
1) Spray early spring with Cornell formula (hort. oil/baking soda)
2) Spray periodically throughout season with neem to control whatever insect it is that's eating my plants
3) Fertilize monthly April - August with some kind of organic fertilizer (alfalfa tea/aged manure/fish emulsion)
4) Add 1/3 c epsom salts 3x season
5) Add a little wood ash to raise pH
6) Prune away dead, damaged wood early spring
Question, if indelicate: can urine be a source of one of the organic fertilizer treatments and if so should I dilute it and how much? Kind of seems like free nitrogen.
By the way I'm not growing sissy roses. Here's the list: William Baffin, Fairy, Bonica, Therese Bugnet, Champlain, Linda Campbell, Constance Spry, R. hugonis and glauca, Felicia, Nymphenburg, Winchester Cathedral.
Thanks for any opinions!