Under The Sea Quilt Block Tutorial

This blog post highlights the Under the Sea quilt block, a simple yet striking design inspired by Benartex’s ocean-themed fabric collection. Using 2 and a half inch strips throughout, the block is easy to cut and assemble, featuring four coordinating prints in the corners and a fussy cut center that showcases unique sea life imagery. The post emphasizes how minimal fabric is needed, how quickly the block comes together, and how the bold background enhances the vibrant colors, resulting in a visually dynamic and beginner-friendly project.

This quilt block is called Under the Sea, and it truly lives up to its name. While the design itself is simple and elegant, the inspiration comes from the fabric collection I used, Under the Sea by Benartex. The colors and prints in this collection feature fish, octopus, and other ocean life, which makes each block feel unique and full of character.

At its core, this is a straightforward and beautiful quilt block. The center square is a focal point, and I chose to fussy cut individual images from the fabric so each block has its own special design. That little detail adds so much personality. The bold black background really helps the vibrant colors stand out, though you could easily swap it for white or another neutral depending on your preference.

One of the things I love most about this block is how simple the cutting process is. Everything is based on 2 and a half-inch-wide strips, which keeps things consistent and easy to manage. For the background fabric, you will need two 2 and a half-inch squares, two strips cut to 4 and a half inches long, and two strips cut to 6 and a half inches long.

For the feature fabrics, choose four different prints. Using a coordinated collection like this one makes it easy because all the fabrics are designed to work together. From each print, cut one 2 and a half inch square and one strip that is 4 and a half inches long. This block does not require much fabric, and you can get a surprising number of blocks from just a small amount. With a quarter yard of each print, you could make quite a few blocks.

To assemble the block, start by laying out your four feature fabrics in the corners. Place your fussy cut center square in the middle, then fill in the remaining spaces with your background pieces. The smaller squares go at the top and bottom, the longest strips sit closer to the outer rows, and the medium strips frame the center.

Once everything is laid out, treat each horizontal line as a row. Sew the pieces together row by row, then join the rows to complete the block. The process is simple, but the finished result is eye-catching and full of life.

This is one of those projects that is quick to make but delivers a big visual impact. The combination of bold color, thoughtful fabric placement, and a striking center makes it a block you will want to make again and again. I hope you enjoy it as much as I did. Follow us on Facebook, subscribe to our YouTube channel, and as always, happy sewing.