I have a knockout rose bush. It sent out branches all season and does not bloom. What do I do??

Question

No photo

Answer 1

Roses don’t bloom if they are stressed or if they don’t get enough sunlight. While you will get some blooms with 5 hrs of direct sunlight, roses prefer 6-8. Are you using a low nitrogen fertilizer? Look for something that has an NPK ratio of 1-3-1 or similar. (e.g. 4-12-6) Too much nitrogen favors leaves over blooms. Roses require an inch of water weekly, 2 inches in hot weather or sandy soil. As temps cool down, roses often pick up their blooming. Look for flower buds. Are they being devoured by insects? Some rose pests are tiny and hard to see but they can cause real damage. Smaller insects seem to favor flower buds and new leaves. Damage may cause the buds to fall off or fail to open. Are there vigorously growing canes that get taller than the rest of the plant; are these coming from the ground instead of the main stem? If yes, kept these cut off at ground level. They are called “blind shoots” and are using up a lot of your plant’s energy. One last thought: has the rose sunk since you planted it? It is very important that the base of the rose be above ground.
I’ve linked to articles that may be helpful:
https://ask.extension.org/questions/135664
https://www.gardeningknowhow.com/ …/knockout-roses/care-knockout-roses. htm