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Elegant Under the Sea Mermaid Birthday Party -by amber's hands-

When you have a girl turning seven, what better way to celebrate than with a mermaid party? This elegant under the sea theme was so much fun and everyone had a blast!

My daughter decided the day after last year’s Tiger Unicorn party that she wanted her next party to be a mermaid party. And she never changed her mind about it, so there was no question about what we were going to do this year!

But even with a plan in place for a year, nothing can ever be simple! We planned for this party to happen on her actual birthday, but found out the day before that someone in my son’s class had tested positive for COVID and so he had to be kept out of school for a week. Because of the risk of potential spread, we pushed the party out a week last-minute.

Thankfully, everyone was still able to make it! It ended up being a blast, even with the unexpected delay.

Mermaid Party

When I was looking for party supplies, I was frustrated to find that any place I went only carried a few items– no single place had enough things to cover all our needs. I also hadn’t planned quite early enough to get everything on Amazon since several things had longer than average shipping dates.

So, last minute as usual, the Tuesday before the party, I drove around town to 5 different stores to get everything we needed. I’ll link to the things I can, but I would suggest planning a little further in advance than I did!

Mermaid Party Decorations

Elegant Under the Sea Mermaid Birthday Party -by amber's hands-

For decorations, we had a few larger things and then primarily let the food do some decorating for us as well.

The biggest thing was the balloons. I got this balloon arch kit from amazon and cut the balloon tape in half. We arranged the balloons with smaller ones at the bottom and larger at the top to mimic the way bubbles get larger the closer they get to the surface of the water.

My sister picked up a piece of sheer aqua fabric at a discount fabric store near her for us to use as a backdrop.

Sea urchin "jellyfish" for mermaid party -by amber's hands-

My absolute favorite part of the decorations were these little “jellyfish” we made float above the table. They’re made with these sea urchin shells and mini air plants. We strung them up with the fishing line that came with the balloon kit.

Elegant Under the Sea Mermaid Birthday Party -by amber's hands-

The cake itself was the main focal point of the table. But I placed it on a shell placemat I found at Hobby Lobby. We used large shells from a collection my parents own, and I found a bag of small shells at Savers for a couple bucks.

I also used flowers in similar colors to the rest of the decor and some greenery that reminded me of seaweed.

Mermaid Party Food

The food was really fun, and not a lot of work. Like I lay out in my Party Planning guide, I focus on one or two bigger, higher impact things and let the rest be easy. So in the case of the food, I focused on the cake and kept everything else very simple.

Mermaid Party food: Meringues, Sixlets, Goldfish
-by amber's hands-

These meringues came out so cute. I’m so happy with them. I love it when I can make meringues work for a party because they’re so easy. I used my recipe for Forgotten Kisses, but swapped the peppermint extract for vanilla and left out the chocolate chips.

To create an ombre effect in the jar, I piped out about 1/3 of the mixture without any coloring. Then I added a little turquoise food coloring to the remaining batter. I then put half of that in the same piping bag I’d used for the white. When that was piped out, I added a little more coloring to the last bit. Using the same piping bag throughout helped transition the color a bit in a really lovely way.

The other great thing about these meringues is that they stay in the oven overnight (with the oven turned off!) so they’re very no-fuss.

Next to those, I put a bowl of parmesan Goldfish. I chose parmesan so the color would be more in-line with the theme.

I also used white Sixlets in an apothecary jar to look like pearls. If you do a lot of parties, I highly recommend apothecary jars! I use them for nearly every party in some way.

Mermaid Popcorn - Mermaid Party 
-by amber's hands-

This mermaid popcorn was also a blast! I used a bag of ready-made popcorn from Trader Joe’s and drizzled it with some pink, purple, and turquoise candy melts (I mixed each of these colors with white to make them more pastel). Then I added some vanilla cupcake goldfish, white Sixlets, and a mermaid sprinkles mix I made myself.

Mermaid Sprinkles -by amber's hands-

I used several different kinds of sprinkles to make this custom mix.

It reminds me so much of sand and seashells!

Mermaid Party Food - grape seaweed
-by amber's hands-

The next easy food item was these grapes on skewers. They have a fun seaweed sort of feel, and my kids helped me put the grapes on the skewers. Super easy!

Mermaid Party Food - Shells & Cheese
-by amber's hands-

And shells and cheese, of course! This is just boxed mac & cheese, made as directed, and put in these super fun holographic bowls.

Mermaid Party Cake -by amber's hands-

And of course, the cake! The cake is where I spent most of my energy. But even still, it was easier than it looks.

My daughter wanted chocolate cake with strawberry filling, so I used my favorite chocolate cake recipe. I always like to use German Buttercream frosting because I think it tastes best, but my go-to recipe isn’t there anymore and I haven’t found a replacement I love just yet. Maybe I’ll have to write my own!

I made the cake sort of a low-key ombre, by making 3 shades of turquoise. I used the lightest on the top and just slightly down the side, the middle color for the center, and the darkest at the bottom. Once I smoothed the sides, they all blended together very nicely without any additional effort.

All the decorations are made from fondant, using fondant molds. I found small containers of fondant in several colors. To make the rainbow accents, I laid the different colors next to each other and twisted them together slightly before pressing into the molds.

There was a bit of a learning curve to using the fondant molds, especially the intricate coral shapes. I found that using vegetable shortening to grease the molds, applied with a food-grade paintbrush to get into all the crevices was key. I also used the thin paintbrush to help carefully peel the shapes out.

To make the whole cake process easier, here’s what I did:

  • Made the cake the week before and kept it in the freezer, tightly wrapped. I let it thaw on the counter the morning of the party.
  • Made the filling and frosting the day before.
  • Did all the fondant shapes the night before. I put them on a cookie sheet with a plastic cover overnight.

Then, the morning of the party I only had to trim the cakes, assemble with the filling, color the frosting, and frost the cake. The fondant shapes then just got pressed on. The shapes that I wanted to have standing up on top of the cake got a toothpick inserted partway into them to create a pick to push into the cake.

Treasure Box Activity & Party Favor

Mermaid Party Favors - treasure boxes with gold chocolate coins
-by amber's hands-

I have learned that at my kids’ parties, most often, the kids just want to play in the back yard. We have a swing set and a little zip line, and that’s really all they want to do.

However, I did have them do one activity that doubled as their party favor. I got these little wooden treasure boxes along with some paint and jewel stickers. I had them each decorate them at the very beginning of the party so they would have time to dry. Then I filled them with gold chocolate coins to take home! Hooray for no cheap plastic junk!

Elegant Under the Sea Mermaid Birthday Party -by amber's hands-

That’s it! I hope our mermaid party gave you some inspiration for your next party!

Adorable and elegant mermaid party for a 7 year old girl! #mermaid #birthday #underthesea #girls #party #birthdayparty
See how we created the perfect mermaid birthday party for our 7-year-old!  #mermaid #birthday #underthesea #girls #party #birthdayparty
An adorable iridescent mermaid party perfect for little girls' birthdays!  #mermaid #birthday #underthesea #girls #party #birthdayparty

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