Question
I BOUGHT A HOUSE A YEAR AGO WITH A BEAUTIFUL ROSE TREE CLIMBING UP
MY HOUSE AT THE FRONT WALK.  I IT BLOOMED ALL LAST SUMMER WITH
LITTLE DELICATE WHITE ROSES - NOT THE FRAGRANT KIND ON A ROSE BUSH.
BY THIS TIME LAST YEAR, IT HAD ALREADY BLOOMED FOR OVER A MONTH,
AND I HAD ALREADY PRUNED IT.  THIS YEAR, THERE ARE NO BLOOMS, AND
VERY LITTLE NEW GROWTH IN COMPARISON TO LAST YEAR.  SOME OF THE
NEW GROWTH LOOKS TO HAVE SHRIVLED UP AND THE LEAVES LOOK LIKE A
WHITE POWDER COVERED THEM. THERE ARE A FEW AFIDS THIS YEAR, BUT I
AM KEEPING THEM IN CHECK. I LIVE IN RENO NEVADA, AND WE DID HAVE
SOME LATE SNOW AND FROST - BUT EVERYTHING ELSE BOUNCED BACK.  
WHAT DO YOU THINK?  THANKS FOR YOU HELP.  SINCERELY, KERRY

Answer
Two things have happened to your white rose. Some roses can be hardy but have tender buds and when there is a late frost it usually kills the buds. If the rose is a once bloomer then it won't have flowers for that year. It also has downy mildew. This dries up the leaves so they don't grow properly. You can try using an organic cure for the mildew but you may have to resort to a rose fungicide. Anything rose product that says it will cure mildew or Black Spot on roses will solve the problem for you. Mildew is hard on a rose as it attacks the new growth but it is usually easy to get rid of. The organic mix is 1 tablespoon baking soda to a 1 quart of water. You have to spray daily until you can see all the mildew is gone and there is new growth coming. Aphids can be discouraged by blasting the rose leaves with the hose. Mature aphids are at the top of the canes. The eggs are laid in the top of the canes and once they are knocked off they are unable to get up again. Birds love them and eat them like candy. Hope this helps.