Three sample versions, real plus-size fit testing, and nearly two months of adjustments — here's how the Strawberry Witch JSK went from its original design to the final Pettilia version.

The original Strawberry Witch JSK has a beautiful strapless silhouette, but its cotton fabric has very little stretch.

When we began developing the plus-size version, we knew that simply adding size wouldn't be enough. We wanted to make the dress more adaptable to different body proportions without losing the character of the original design.

From our first discussion with Strawberry Witch and the pattern makers to final approval for production, the process took about two months and three sample versions.

The Development at a Glance

Here's what changed — and why.

Version 1: Adding Adjustable Shoulder Straps

The original JSK has a strapless bodice, short back zipper, and no shirring. Because the fabric itself has very little stretch, our first idea was to add adjustable shoulder straps for more flexibility.

We discussed the idea with Strawberry Witch and the pattern makers, made the first sample, and tested it on a plus-size fit model.

The straps worked functionally — but once we saw the dress on a real body, something didn't feel right.

They changed the visual balance of the dress and took away from one of its defining features: the clean strapless silhouette.

The first sample was wearable. But "wearable" wasn't enough.

So instead of accepting the easier solution, we went back to the brand and pattern makers and started again.

First development sketch — the adjustable shoulder strap version

Version 2: Adding Flexibility Where It Was Really Needed

For the second version, we asked a different question:

Instead of changing the shoulders, could we create more flexibility through the back construction?

We kept the original strapless silhouette and introduced an extended shirred panel at the back.

This gave the bodice more adaptability while keeping the front and overall character much closer to the original Strawberry Witch design.

Second development sketch — the shirred back version

Then we tested the new sample again with plus-size fit models.

The result was much closer to what we wanted — but the fitting also showed us two more details that needed work:

The skirt felt slightly short on some tall bodies, and the waist adjustment needed more flexibility.

So we made a third sample.

Version 3: Refining the Details

Sometimes the biggest difference comes from relatively small changes.

A Longer Skirt

We adjusted the skirt length to create better overall proportions on the plus-size version.

More Flexible Waist Adjustment

The original design had three waist belt loops.

We changed this to four, giving the wearer more options for positioning the waist belt according to her natural waistline, body proportions, and preferred fit. We also slightly lengthened the waist belt for each plus-size size to give more room for adjustment and a more comfortable fit.

After these changes, we made another sample and carried out another fit test before approving the design for production.

Final sample — the approved plus-size version

Checking the Actual Garment

Fit testing doesn't end with the pattern.

Throughout development, we also measured the physical samples by hand to confirm that the finished garment matched the measurements we intended.

For this dress, we checked key areas including:

Bust · Waist · Skirt Length · Shirring

Bust

Bust measurement — Strawberry Witch JSK plus-size sample

Waist

Waist measurement — Strawberry Witch JSK plus-size sample

Skirt Length

Skirt length measurement — Strawberry Witch JSK plus-size sample

Shirring

Shirring measurement — Strawberry Witch JSK plus-size sample

These measurements were part of our final checks before the dress moved into production.

What Changed From the First Sample to the Final Version?

More Than Simply Sizing Up

This dress is a good example of why plus-size development isn't simply about adding centimeters to an existing pattern.

Measurements matter, but so do more fabric used, a fuller lining, proportion, construction, flexibility, movement, waist placement, and how the garment actually feels on a real body.

For the Strawberry Witch JSK, we didn't need to redesign the entire dress. We needed to identify where the original construction worked — and where it needed to change for plus-size bodies.

There is no single formula we can apply to every design.

Each piece has to be considered, sampled, fitted, and adjusted individually.

Two Months. Three Samples. One Final Dress.

Behind the finished Strawberry Witch JSK were approximately two months of discussions, pattern adjustments, three sample versions, physical measurements, and repeated plus-size fit testing.

Measure. Try. Adjust. And try again.

Our goal isn't simply to make an original dress larger.

It is to make it work better for plus-size bodies while preserving the design that made us love it in the first place.