How to Prune sweet briar?
Keep single-flowering shrub roses lightly pruned, removing dead, diseased, crossing and weak growth. Thin a few old unproductive stems if crowded. Prune in late summer after flowering.

sweet briar · Rosa rubiginosa
Also known as: sweet brier; eglantine
Grow in fertile, humus-rich, moist but well-drained soil in full sun. Mulch with well-rotted organic matter in late winter or early spring, and for best flowering apply a general rose or shrub fertiliser in early spring and again in early summer. See rose cultivation. Tolerant of poor soil and shade, suitable for hedging
Keep single-flowering shrub roses lightly pruned, removing dead, diseased, crossing and weak growth. Thin a few old unproductive stems if crowded. Prune in late summer after flowering.