Lilac Butterfly Open-Back Top Crochet Pattern

This butterfly top is wearable art, and I am so excited to share it with you! One large butterfly motif forms the entire back of the garment: two rounded upper wings spread toward the shoulder blades, two smaller lower wings taper toward the waist, and a raised segmented body joins all four wings at the centre back, complete with curled antennae.

I will be honest with you, this is not a quick weekend project. It uses tall stitches like trebles and double trebles, lace construction with chain spaces, and three-dimensional elements. But if you have been craving something showstopping for your handmade wardrobe, something that makes people stop and ask if you really made it, grab your hook and let us dive in.

The instructions below describe the Medium sample in full. To resize, add or subtract one repeat in the radiating sections of each wing and adjust the side band rows to your body measurement. Many of the lace rows are worked as repeats across the row and carry no closing stitch total in the original pattern, so I have reproduced those rows exactly as written.

Materials

• 260 to 420 yards sport/5-ply mercerized or matte cotton yarn in lilac (main colour)
• 70 to 110 yards of the same weight cotton yarn in pale ivory (contrast 1)
• 25 to 45 yards of the same weight cotton yarn in plum (contrast 2)
• 3.0 to 3.5mm crochet hook, chosen to meet gauge
• Tapestry needle
• Stitch markers
• Scissors
• Blocking pins and mat
• Optional: a small amount of 1 to 2mm elastic thread for the side bands

Abbreviations

• ch: chain
• sl st: slip stitch
• sc: single crochet
• hdc: half double crochet
• dc: double crochet
• tr: treble crochet
• dtr: double treble crochet
• sp: space
• sk: skip
• st/sts: stitch / stitches
• RS/WS: right side / wrong side
• rep: repeat
• FO: fasten off

Special Stitches

• 3-dc shell: work 3 double crochet stitches into the indicated stitch or space, creating a small fan shape
• 5-dc fan: work 5 double crochet stitches into the indicated chain space, creating a larger, more dramatic fan
• Picot: chain 3, then slip stitch into the first chain you made, creating a small decorative loop
• Front-post rib (FPtr): yarn over twice, insert your hook from front to back to front around the post of the indicated stitch, then complete the treble as usual
• Bobble segment: (yarn over, insert hook in stitch, yarn over and pull up a loop, yarn over and pull through 2 loops) 5 times in the same stitch, then yarn over and pull through all remaining loops on your hook, chain 1 to close
• Cord: chain to your desired length, then slip stitch into the back bump of each chain, creating a firm, rounded tie that will not stretch out

Gauge & Size

• Gauge: 20 dc and 10 rows = 4 inches in solid fabric, after wet blocking; one completed upper wing before edging should measure about 7.5 inches from body join to outer tip in the sample size
• Sizes: XS/S bust 30 to 34 in, butterfly 12.5 to 13.5 in wide; M bust 35 to 38 in, butterfly 14 to 15 in wide; L bust 39 to 42 in, butterfly 15.5 to 16.5 in wide; XL/2X bust 43 to 48 in, butterfly 17 to 18.5 in wide
• Construction: four wings worked separately, joined around a centre spine, finished with a raised body, accent borders, side bands and neck ties, then wet blocked
• Skill level: Intermediate to Advanced

Upper Wing Pattern (Make 2)

Make the first wing as written. For the second wing, work the same pattern and reverse the joining orientation during assembly so the pair mirrors cleanly.

Row 1 (RS): With lilac, ch 9. Dc in 4th ch from hook and in next 5 ch. (7 dc including turning ch) Turn.

Row 2: Ch 3, dc in same st, 2 dc in each of next 5 sts, 2 dc in top of turning ch. (14 dc) Turn.

Row 3: Ch 4, tr in next st, ch 2, sk 1, tr in next 2 sts across, ending tr in last st. This creates the first open rib row. Turn.

Row 4: Ch 3, dc in first tr, 3 dc in ch-2 sp, dc in next 2 tr across. Turn.

Row 5: Ch 5, dtr in same st, ch 2, dtr in next dc, ch 2, sk 1 dc across. Finish with 2 dtr in last st. Turn.

Row 6: Ch 3. Work 2 dc in first ch-2 sp, then 3 dc in each ch-2 sp across. Work 3 dc in final edge space. Turn.

Row 7: Ch 4, tr in same st, ch 1, tr in next 2 sts, ch 2, sk 1, tr in next 3 sts, ch 2, sk 1 across. Finish 2 tr in final st. Turn.

Row 8: Ch 3, dc in each tr and 3 dc in each ch-2 sp. Turn.

Row 9: Ch 5, dtr in same st, ch 2, dtr in next 2 sts, ch 3, sk 2 sts across, placing 2 dtr in last st. Turn.

Row 10: Ch 3, 2 dc in each ch-2 sp, 5-dc fan in each ch-3 sp, and dc in each dtr between spaces. Turn.

Row 11: Ch 4, tr in first st, ch 2, sk 2 sts, tr in next st across, working 2 tr in the final st. Turn.

Row 12: Ch 3. Work 3-dc shell in each ch-2 sp, sc in each tr between shells. Do not fasten off.

Outer wing shaping: Rotate the work 90 degrees. Crochet evenly around the curved outside edge only: sc in next row-end, ch 2, sc in next row-end around. At the top shoulder point, work (sc, ch 3, sc) to create a defined tip. Stop at the lower inner corner and FO, leaving a 12 in / 30 cm tail for assembly.

Size adjustment: to enlarge, repeat Rows 9 and 10 one additional time before Rows 11 and 12. To reduce, omit Row 9 and work Row 10 using 3-dc shells instead of 5-dc fans. Make both upper wings identical.

Lower Wing Pattern (Make 2)

The lower wings are smaller and more tapered. They should visually echo the upper wings without matching them exactly.

Row 1: With lilac, ch 7. Dc in 4th ch from hook and in next 3 ch. (5 dc including turning ch) Turn.

Row 2: Ch 3, dc in same st, 2 dc in next 3 sts, 2 dc in top of turning ch. (10 dc) Turn.

Row 3: Ch 4, tr in next st, ch 2, sk 1, tr in next st across. Turn.

Row 4: Ch 3, 2 dc in each ch-2 sp and dc in each tr. Turn.

Row 5: Ch 5, dtr in same st, ch 2, sk 1, dtr in next st across, 2 dtr in last st. Turn.

Row 6: Ch 3, dc in each dtr, 3 dc in each ch-2 sp. Turn.

Row 7: Ch 4, tr in same st, ch 3, sk 2 sts, tr in next 2 sts across, ending 2 tr in final st. Turn.

Row 8: Ch 3, 5-dc fan in each ch-3 sp, sc between fans. Turn.

Row 9: Ch 3, dc in next 3 sts, ch 2, sk 1 across. Turn.

Row 10: Ch 3, dc in each dc and 3 dc in each ch-2 sp. FO, leaving a 12 in / 30 cm tail.

Lower edge shaping: Join lilac at the widest outer corner. Work sc evenly around the curved outer edge, placing a ch-2 between every second or third sc to keep the lace open. At the lowest point, work (sc, ch 3, sc), then continue to the inner corner. FO.

Assembling the Butterfly

For the centre spine, with lilac, ch 33. Beginning in 2nd ch from hook, sl st in each ch across. This firm cord is the centre spine.

Lay the cord vertically on a blocking mat and mark four attachment zones: upper-left wing, upper-right wing, lower-left wing and lower-right wing. Pin the upper wings so their inner lower corners meet near the upper third of the spine. Pin the lower wings beneath them with a 1/2 to 1 in / 1.5 to 2.5 cm visual gap between the upper and lower lobes.

Using the long lilac tails and a tapestry needle, whipstitch each wing to the spine through sturdy stitch posts rather than through chain spaces, making 5 to 8 secure attachment points per wing. Keep the wings flat and symmetrical, and do not pull so tightly that the centre gathers.

At each side, tack the lower inner edge of the upper wing to the upper inner edge of the lower wing in 2 to 3 places. Leave the majority of the gap open so the butterfly remains visibly divided into four wings.

Before adding the body or borders, pin the butterfly flat and compare left and right. The upper tips, lower tips and outermost points should align horizontally. Correct any asymmetry now by easing stitches at the join.

Butterfly Body & Antennae

Work the body directly over the centre spine so it stands slightly above the wing surface. Join lilac at the top of the spine and work 5 sc around the cord, then turn.

Row 2: Ch 1, bobble segment in centre sc, sc in remaining sts. Turn.

Row 3: Ch 1, sc across. Turn.

Repeat Rows 2 and 3 three more times to create four rounded body segments.

Tapered tail: Work 4 sc, then 3 sc, then 2 sc over the next three short rows. FO and weave in securely.

Antennae: Join lilac at the top-left of the first body segment. Ch 13, then work 2 sc in each of the final 5 chains to force a curl. Sl st back along the remaining chains. FO. Repeat on the top-right, mirroring the first antenna, and block the curls with your fingers rather than pinning them straight.

Borders & Edging

Plum accent border: with RS facing, join plum anywhere on an outer wing edge. Work sc evenly around the entire perimeter of that wing, placing 2 sc in each outer tip and 2 sc in every ch-3 point. Across deep inward curves, use sl st or skip one underlying stitch as needed so the border lies flat. FO and repeat for the remaining three wings.

Ivory scallop and picot edge: join pale ivory into any plum sc. Skip 1 plum sc, 5 dc in next plum sc, picot, skip 1 plum sc, sl st in next plum sc. Repeat around the wing. At narrow tips, work 7 dc instead of 5 dc so the scallop wraps smoothly around the point. At deep concave joins near the body, substitute (sc, picot, sc) for a full shell to avoid crowding. FO. Repeat around all four wings.

If the edge ruffles, use fewer shells or skip an extra plum stitch between shells. If it cups inward, add an extra shell at each broad curve. The border should lie flat after blocking.

Side Bands & Neck Ties

Side bands (make 2): join lilac at the inner outer edge of one lower wing, beginning about 1.5 in / 4 cm above its lowest point.

Row 1: Work 18 sc evenly along the attachment edge. Turn.

Row 2: Ch 2, hdc across. Turn.

Rows 3 to 8: Repeat Row 2, or continue until the band reaches from the butterfly edge to your side seam without stretching more than 10%.

Optional shaping: decrease 1 hdc at each end on the final two rows for a tapered side seam. FO, leaving a long sewing tail, and repeat for the second side. For a tie-back version instead of sewn side seams, continue each band as a cord: ch 70 to 90, then sl st back along the chain, and tie at the front or side.

Neck ties: join lilac at the top point of one upper wing. Ch 95 to 115, depending on your desired tie length. Sl st in the back bump of each chain to form a firm cord. FO. Repeat at the opposite upper wing. As an optional decorative end, add a tiny 5-petal flower by working (ch 3, 2 dc, ch 3, sl st) five times into a magic ring, and sew one flower to each tie end.

Finishing & Assembly

Weave all yarn ends through solid stitch posts for at least 1.5 in / 4 cm, reversing direction once before trimming. Soak the top in cool water with a small amount of wool or cotton wash for 10 to 15 minutes. Do not wring it. Roll it in a towel to remove excess water, then pin the butterfly flat, matching the left and right wing dimensions. Pin every scallop point and picot lightly, shape the centre body straight, and leave the antennae softly curled. Allow it to dry completely before unpinning.

Care: hand wash cool, reshape while damp and dry flat. Do not hang the top while wet, because the open lace can lengthen. Store folded.

Tips

Measure your back width from the outer edge of one shoulder blade to the other before you start. Your finished butterfly width should be about 85 to 95% of that measurement, since the side bands and ties provide the remaining fit.

If the wings curl upward, add one extra stitch at the widest curves during the plum round, then block firmly. If the butterfly sags at the centre, add two more whipstitch attachment points per wing and reinforce the spine.

If the side bands stretch too much, use a smaller hook for the bands or carry fine elastic thread through the final two rows.

Before you call this project complete, check that all four wings mirror cleanly and lie flat, the plum accent line is continuous, the body is centred and slightly raised, and the neck ties are equal in length.