To gather fabric evenly, sew two parallel rows of long straight stitches, 4 to 5 mm long, without backstitching, pull the two bobbin threads together to draw the fabric up, then pin it to the shorter edge at matching quarter marks and spread the folds evenly between them. Sew the seam with the gathered side on top, between the two rows, so you can stop any fold from being pinched into a pleat.
How much fabric do you need to gather?
The gathering ratio is the length of the edge before gathering divided by its length after. It decides how full the result looks:
| Ratio | Look | Typical use |
|---|---|---|
| 1.3 to 1.5 | Soft, gentle fullness | Skirts in medium-weight cotton or linen, sleeve heads |
| 1.8 to 2 | Classic gathered skirt | Dirndl and tiered skirts, dress skirts |
| 2.5 to 3 | Very full, frilly | Ruffles in light fabrics, petticoats |
Light fabrics (voile, lawn, viscose, double gauze) gather beautifully at high ratios; thick fabrics (denim, canvas, wool) look bulky above 1.5. Sewly's gathered skirt lets you choose the ratio from 1.3 to 3, with 1.8 as the default, and its fit-and-flare dress offers a gathered skirt from 1.3 to 2.8. To work out a cutting width yourself, the gathering ratio calculator does it for any length and ratio.
Choose a gathering method
- Two rows of long stitches: the standard, and it works on nearly every fabric. Described step by step below.
- Zigzag over a cord: for long edges and thick fabrics. Lay a strong cord (crochet cotton, dental floss, buttonhole thread) along the allowance and zigzag over it without catching it. Pull the cord: it never snaps.
- Elastic: for casings and cuffs. That is a different technique; see how to sew an elastic waistband casing.
- Gathering foot or serger differential feed: quick if you have them, but less adjustable once sewn.
How to gather fabric with two rows of stitches
- Sew the joining seams first. Sew and finish the side seams of a skirt or the short seams of a ruffle, so you gather a continuous loop.
- Set the machine. Straight stitch, 4 to 5 mm long (5 to 6 stitches per inch). Tighten the needle tension by one step if you like; it makes the bobbin thread slide more easily. Use a strong polyester thread, ideally in the bobbin too.
- Sew the first row. With a 1.5 cm (5/8 in) allowance, sew 1 cm (3/8 in) from the raw edge, right side up, without backstitching, leaving thread tails of 10 cm (4 in) at both ends.
- Sew the second row 2 cm (3/4 in) from the edge, parallel to the first. The seam will run between the two rows, at 1.5 cm, which keeps the gathers straight and upright.
- Break long edges into sections. On an edge longer than about 1 m (40 in), stop and start new rows at each seam or every 50 cm (20 in). Shorter threads are far less likely to snap.
- Mark the quarters. Fold the edge to be gathered in half, then in half again, and mark the folds with pins or small snips. Do the same on the edge it will be sewn to: the waistband, the bodice or the upper tier. On long edges, mark eighths.
- Pin the marks together. Right sides together, pin the piece to be gathered to the flat piece at each mark and at the seams.
- Pull the bobbin threads. Hold both bobbin threads of one section and slide the fabric along them, working from both ends toward the middle, until the section fits. Wind the tails around a pin in a figure eight to hold them.
- Distribute the gathers. Spread the folds evenly with your fingers or a pin, keeping them at right angles to the edge. Pin every 2 to 3 cm (3/4 to 1 1/4 in).
- Sew the seam. Set the stitch back to 2.5 mm (about 10 per inch) and the tension back to normal. Sew at 1.5 cm (5/8 in), gathered side up, between the two rows. Stop every few centimeters with the needle down and flatten the folds in front of the foot with a pin so none get turned over.
- Remove the visible row. Pull out the row at 2 cm (3/4 in), which would show on the right side. The row inside the allowance can stay.
- Finish and press. Finish the allowances together with a zigzag or serger. Press the seam allowance away from the gathers, toward the waistband or bodice, pressing only the allowance with the tip of the iron: about 200 °C (390 °F) for cotton and linen, 150 °C (300 °F) for viscose, 110 °C (230 °F) for polyester. Do not flatten the gathers themselves.
Tip: Sewing with the flat piece against the feed dogs and the gathers on top lets you see every fold before it reaches the needle.
Gathering thick fabric and long ruffles
For denim, corduroy, wool, or a ruffle several meters long, use the cord method. Zigzag over the cord with a wide stitch, about 4 mm wide and 3 mm long, 1 cm (3/8 in) from the edge, wrap one end of the cord around a pin, and pull the other end. Remove the cord after sewing the seam. Then reduce the bulk: trim the gathered allowance to 6 mm (1/4 in) and leave the other one wider, so the seam steps down instead of forming a ridge.
Gathering tiers and ruffles
On a tiered skirt, each tier is gathered onto the bottom of the one above it, so you repeat the whole process once per seam. Work from the top down: attach the second tier to the first, then the third to the second. Mark quarters on every tier; the lower tiers are longer and that is where uneven gathers show most. For a hem ruffle, gather it in sections between the side seams and pin it to the hem with the gathers on top, then press the allowance up toward the skirt so the ruffle hangs down freely.
Gathering by hand
For a small area, such as the top of a puff sleeve on a child's dress or a doll's skirt, hand gathering is quick and very controllable. Use a doubled thread knotted at one end, and sew a running stitch of 3 to 5 mm (1/8 to 3/16 in) along the line, then a second row 6 mm (1/4 in) away. Pull both threads together and wind them round a pin, exactly as with machine rows.
Common mistakes and fixes
- The thread snaps while pulling. The section is too long or the thread too weak. Sew the rows again in shorter sections with polyester thread, or switch to a cord.
- Gathers bunched in one place. The quarter marks were skipped. Unpin, mark quarters and eighths on both pieces, and redistribute.
- Small pleats caught in the seam. Folds turned over under the foot. Unpick that section, flatten the folds, and sew it again slowly with the gathers on top.
- Gathering stitches show on the right side. The outer row was left in, or the seam was sewn outside the rows. Remove the visible stitches with a seam ripper.
- A bulky waist. The ratio is too high for the fabric. Trim and grade the gathered allowance now, and use a lower ratio next time.
Gathers are what make a gathered skirt or a ruffle look soft and full, and you will use the same rows of stitches for puff sleeves and tiered dresses.