Leave all ends of Color B dangling until the end, your starting strand and ending strand. “Join with FPtr” is called a standing stitch and there are YouTube videos.
Row 4 Back and Front:
Row 8 Front and back: (Row 8, the x 3 after the bracket should be x 4)
Row 11 with leaves snugged up to stalk using the loose ends of your color B. Take your darning needle and as you bury your ends bring the leaves snug with the stalk. You want it to mimic the long stalks with leaves in the rest of the design.
Row/Round 12 with sc worked around 3 sides and then into raw edge.