Something I came up with based on looking at various crochet rug patterns online. These are more notes I made as I went along than a well-written pattern, so let me know if something doesn’t work or doesn’t make sense.
Hook: 5.0 mm (H)
Yarn: Lily Sugar’n Cream Cone (less than one), Key Lime Pie
Pattern: ch 36 (or multiple of 4 to make about 10”).
Row 1: sc in 2nd ch from hook, hdc, dc, hdc, sc, hdc repeat from * across, 35 sts. ending with dc. ch 1, turn.
Row 2: sc in 1st dc, hdc, dc, hdc, sc, hdc, dc repeat from * across, 35 sts. ch 1, turn.
Repeat row 2 until 28” (76 rows)
Border: ch 1, turn, sc in next 34 sts, 3 sc in last st. rotate (don’t turn) and continue working down side for 99 sts (use more or fewer to make sure the piece lies flat), 3 sc in corner, 33 st across bottom working between sts, 3 sc in corner, 2 sc in last space, join to first sc with sl st. (276 sts: 33 on 2 ends 99 on 2 sides, 3 in each corner)
If you want the rug to have a clear right/wrong side, work remaining border with the same side facing, otherwise turn the piece at the beginning of each row.
Continue working in sc rounds, turning each row if desired, working either (3 sc) or (sc, ch 2, sc) in corners, which increases each round by 8 sc.
Note: I think I should have only used ch1 instead of ch2 in the corners, because it came out just a bit pointy.
For row 15, I worked (Ch 1, draw up a loop in first 2 sts, yo and draw through all 3 loops on hook, * draw up a loop in same st as last leg of last st and in next st, yo and through all 3 loops on hook; repeat from * across; sc in same st as last leg) increasing in corners, total 384 sts. end off. (from row 2 of Crochet Natural Stripes Rug Crochet Pattern)