Question
I live in Trenton Ont. Canada zone 5.  I made a rose garden for my wife of 54 years and this developed this year.  The tips of the new shoots just befor they develop buds go dark brittle and die. I only have 38 roses in the garden and it seems to only effect some of them.  We have had a lot of rain this year.The garden gets all day sun.  I have sprayed for Black spot early in the year when a few of the plants started to show it.It does ot seem to hurt the plants but no blooms. Thanking you in advance  Jack

Answer
It sounds like you have rose midges eating your rose buds. Feeding by the larvae causes bent, misshapen, or blasted buds and withering stem tips. Flower buds and growing shoots turn brown and finally black. with a magnifying lens, look for the small whitish larvae between the petals and sepals at the base of the flower bud to verify the presence of midge larvae. Prune out these infested buds to remove the larvae, reducing the number of midges available to re-infest the plants. Midge damage is often noticed after July. Chemical control is needed for persistent problems. Systemic insecticides are the best choice. Acephate (Orthene) and dimethoate (Cygon-2E) are systemic chemical controls. Be sure to get good coverage of flower buds.
There is anther possibility in that a cold snap could have killed the buds before they had a chance to open but it would have killed more than a few rose buds. It sounds more like rose midge.