What they're saying is that the section of stem you cut with the flowerhead and leaves beneath it serves to prune the shrub back as well. Same as when cutting roses for indoor display during summer.

"Most are best left unpruned: they are very susceptible to dieback, which pruning can encourage. D. odora tolerates light trimming to maintain a compact habit"

--Brickell/Joyce, PRUNING & TRAINING (1996, DK Publishing, New York)

Thanks, bboy. The flower clusters make sense; I was just wondering about keeping it compact with that overly long branch. It's about 2' when the other branches are only 6". Would cutting it back to 12" constitute "light" trimming? Or should I just trim the flowers and it will correct itself?

Branch having 12" cut off might not sprout back well. Leaning flattish habit typical of this shrub.

OK, thanks. I'll prune as indicated, let it grow, and see if it evens out.

Bumping this up with a new question. I have a couple of D. odorata in front of my house (north facing). In the last 1-2 winters there has been more substantial dieback. I pruned out a bunch of dead stuff a couple of months ago. It's bloomed already and is now leafing out. There are some pretty empty areas... not quite dead, but very little growth. Are those salvageable? Should I just cut them back to the base and accept having a lumpier shaped shrub?

These plants were very happy from when I bought the house (2005) until either this winter or last winter, when I started noticing these empty zones with less foliage, flower, growth.

-Greta

When should Daphne be prune?

Daphnes, especially D mezereum do not like to be pruned at all, so there is no 'should' about it. Unless there is a very good reason, such as removing dead branches, I would leave all Daphnes alone. They resent transplanting and should only be pruned when absolutely necessary. If you must prune do it incrementally, do it in dry weather just after flowering and observe strict hygiene by cleaning your pruners and even using fungicide on the cuts.

The traditional advice regarding daphne pruning is exactly as flora_uk says, don't do it unless it's absolutely necessary. Interestingly, commercial growers - at least the ones I've seen - pretty much do the opposite. They routinely shear d. cneoreum and other varieties to keep the plants tight and bushy and manageable as potted or b&b plants. They do it right after they have bloomed.