Answer: The normal size range for this rose is three feet tall and wide, so it sounds like your plants were growing in that pattern. Pruning them back fairly short in late winter or very early next spring should help them stay dense and bushy for the next growing season.
As far as Japanese beetles go, there really is not a lot we can do as gardeners. They are a terrible pest and roses are one of their favorite foods, unfortunately. Some gardeners report success using a spray containing neem as a repellent. Handpicking early and late in the day when they are sluggish can also help somewhat. Do not however use the pheromone traps as these tend to lure more into the area than they catch.
Enjoy your roses next summer!
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