Question
I let my zinnias seed and the tall ones came up toward the front of my beds.  They are so tall and heavy they are falling over.  My question is how to prune.  They are approx. 3 ft. tall. They are full of blooms and I have trimmed all the dead flowers just need to know how aggressive do I get with the plant.  Thanks

Answer
Val,
The thing is, there is no way that you can keep them short.  Every plant is genetically programed to be a particular size and shape, and when you cut a lot off, the plant's response is to immediately make more to replace what it's lost.  So although you can cut any of the zinnia stems down by 2/3, the plant will replace what you cut off in a couple of weeks.

At this point you can do any of the folowing:
Stick thin bamboo stakes in along the edge, putting them in at 45 degree angles (some pointing left and some right) so that they cross each other and make an attractive and supportive fence to prop up the zinnias.

Keep cutting zinnias for bouquets - it will at least keep them in check and keep zinnias on your table.

Pull up the plants (a weed is any plant out of place - including zinnias!)

Let them flop and ignore them for this year - know that when you see seedlings next spring, to transplant them to the middle or rear of the garden.

all the best,
C.L.
www.gardenlady.com