Why do my rose buds look like this?

High Humidity

Unfortunately, roses with a higher petal count- for example: peony or cabbage-shaped roses- may not be the best choice for those of us in high-humid areas. Rose buds can ball under high humid conditions.

Thrips

To test for thrips, snip off an affected bud and shake over a piece of solid-colored paper (or another flat surface). If there are very tiny critters that look like little specs upon first glance, you have thrips on your roses! The good new is, thrips are very rarely fatal to roses- they just may not have the most aesthetically pleasing outcome. Thrips are worse some seasons than others, and are very difficult to impossible to get rid of because of their small size and hiding tendencies. You can attempt to reduce their effects by removing and discarding the affected buds and spraying new buds with neem oil.

Downy Mildew

Downy Mildew has several symptoms, including purplish-red, brown, or black spots (not to be confused with the fungal disease, Black Spot), grayish growth on the underside of leaves, browning of flowers, and balling or collapsing of buds. It typically occurs during the spring in cooler, damp conditions. To prevent Downy Mildew, try your best to prevent water from getting on the leaves, promote good air circulation by pruning, remove affected debris from the area, and treat with fungicide if symptoms appear.