This beautiful pattern from 1902 by Butterick is called an insertion but would make a great accent stripe in an afghan! I reworked the decreases and stitch positions to make the leaves more defined.
There’s a quickly-memorized 6-stitch header on each side of the 21-stitch leaf section. Row 1 starts near the tops of the leaves and the knitting works toward the leaf stems. The short edges won’t block straight without set-up short rows but these are optional.
Skills needed include short rows, yarn overs, double yarn overs and decreases: k2tog, SSK, k3tog and S2KP2.

9 sts/inch and 13 rows/inch for 33-stitch rose leaf swatch blocked with #10 crochet thread and #2 needles
Gauge is not important; any block-able thread/yarn and size needles will work. Make a swatch to check for looks and width.

8 yards of #10 crochet thread will make one 16-row repeat of this pattern in the gauge above.

A matching edging is posted separately.