We buy rosebushes typically for the beauty their blooms will add to rose beds, gardens or landscaped areas. Thus, it is cause for major frustration when they do not bloom. In some cases, roses will form nice big buds or clusters of buds, then seemingly overnight the buds appear to wilt, turn yellow and fall off. Knock Out rosebushes are no different when it comes to this frustration. There are several reasons why these roses may not bloom, so let’s take a look at some of them. CONTINUE
SOURCE: https://www.gardeningknowhow.com/ornamental/flowers/knockout-roses/knock-out-roses-wont-bloom.htm