Is it possible to pinch back some of the larger zinnias and get them to branch and have more blooms? Here they grow 5 or 6 feet tall before they bloom. I like the nice large blooms, but not that height.
pinching back zinnias
You can indeed pinch zinnias to get them to branch and re-branch. However, if your zinnias are growing 5 or 6 feet tall, they are probably too close together. Some varieties of zinnias, Burpee's Burpeeana Giants for example, like to spread out some to form a bush. So give them room to spread, and don't make them compete with each other to stretch for sunlight.
I breed zinnias as a hobby, and this home-hybridized zinnia in the picture was unusual this year, because it had an extreme spreading tendency. That zinnia in the picture is just one plant and, depending on where you measure it, the plant is up to 5 feet across and has dozens of flowers open at once. I refer to it as my "shrub zinnia" and I have crossed a number of different zinnias onto it in an effort to get a whole lot more of these shrub zinnias in a variety of flower forms and flower colors. The shrub zinnia trait may not persist, but I can hardly wait until next year to see how those crosses will turn out. Incidentally, if you give Burpeeana Giants room to spread, it is not unusual for their plants to be wider than they are tall.
I don't call it "pinching back" I just cut lots of flowers for indoors! Keeps them busy. And yes, the one that was growing alone is the bushiest of all!
thanks both of you. Sorry I didn't answer sooner, but some health issues kept me pretty lazy for awhile.