I also pruned two yews way back this past spring to see if they would grow back. It took a long time to see any new growth. I was ready to dig them out but they were in a spot in our backyard that wasn't readily seen. So I left them. Finally one started growing and now doesn't look too bad but the other one only half-grew new shoots so it looks kind of funky. I'll decide what to do with them next season. I was telling people (at Master Gardener booths when I volunteer to answer questions) that you can cut back yews and they will return but now I say 'sometimes they will resprout.' Those darn plants don't follow the rules! - L.D. -
If you cut a shrub back because it's just too big, and it dies, you haven't lost anything but a plant that couldn't live by your rules. - Janet -
Here are yews we cut back in a year when the shrubs did behave as usual.
On April 1 before growth began, we cut this yew to 6" stubs. It was totally devoid of green. (Sorry; we didn't take photos. Reality is that we do this work for a living and can't always afford to take the time to capture everything on film, or wait for a day with the right lighting...) This photo was taken June 1 of that same year.
We cut it back because it was just too big for the spot. How big was it? As large as the uncut yew on the right.
Before we cut it back, it was covering half the sidewalk -- see the stain where the pavement was covered? (Arrow)
Notice, too, that the still-large shrub is not actually as big as it was. On April 1 we had cut it, too, but we cut only half its branches to the ground. We figured we'd see what difference it might make to do as English gardeners advised us, "Cut back half at a time."
As you can see here, it made little difference. Both plants did sprout new within 8 weeks. If there's a difference, it's that the plant cut totally bare came back better.
We ended the experiment by cutting the rest of the still-big yew back on June 1. That late-cut portion, too, grew back that same year. Now, ten years later, both plants continue healthy. We prune both annually to keep them from encroaching on the sidewalk, and so have not had to deal with such overgrowth again.
Cutback shrubs stall
What's Up 165: Precocious bloom waning jade orchids Alabama