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rhubarb poke cake

Beautiful Rhubarb Poke Cake — Summer In a 9x13 Pan

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Last Modified: May 14, 2026
Published: May 14, 2026

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Starts With A Cake Mix, Ends Up a Show-Stopper

Are you looking for a summer dessert that is easy, fast, and looks like you really fussed over it? I thought so! Try this amazing rhubarb poke cake! It ticks every box! This is especially great if your rhubarb is doing what mine is....growing and producing like crazy! Lucky you if a neighbor gave you some!

Why You'll Love This Rhubarb Poke Cake

  • Fast and easy to pull together
  • Cold, creamy, and perfect for warm weather
  • Pretty enough for company without a lot of fuss
  • Half Simple Simon and half Fancy Nancy
  • Make-ahead friendly and even better after chilling

If you're a rhubarb fan like me, here are some more reader favorites:

One-Bowl Rhubarb Bread

Rhubarb Custard Pie

Rhubarb Dump Cake

How To Make This Pretty Rhubarb Poke Cake

1. Make the rhubarb topping

Combine the diced rhubarb and sugar in a saucepan and let it rest for an hour or so. This helps draw out the juices and softens the rhubarb before cooking.

Add the water and simmer gently until the rhubarb is completely tender and beginning to break down. Stir in the strawberry gelatin and keep stirring until it dissolves completely. Set the topping aside while the cake bakes.

Reserve about 1/2 cup of the topping to decorate the cake later, if desired.

2. Bake the cake

Prepare the cake mix according to the package directions and bake in a greased 9x13-inch pan at 350 degrees.

Bake until the top springs back lightly when touched, the edges begin to pull away from the pan, and a cake tester comes out clean.

Don’t underbake — the cake needs enough structure to hold the filling. The edges of the cake should start pulling slightly away from the pan.

3. Poke and fill

While the cake is still hot, use the handle of a wooden spoon to poke holes all over the surface.

Slowly spoon the warm rhubarb topping over the cake, using a rubber spatula to gently spread it around and encourage it down into the holes. This is where all that wonderful flavor sneaks into the cake.

Refrigerate the cake until completely chilled and set, at least 2 hours.

4. Frost and decorate

Helpful hint: For the fluffiest topping, thaw the whipped topping in the refrigerator overnight or for several hours while the cake is cooling. Don’t microwave it or leave it sitting out on the counter too long - it can lose volume and become runny.

Spread the whipped topping evenly over the chilled cake, going all the way to the edges.

If you’d like to add the pretty swirled top, drizzle a few thin lines of the reserved rhubarb topping across the whipped topping. If the topping has thickened too much, stir in just a tiny splash of warm water to loosen it slightly.

Drag a table knife gently through the lines in one direction and then the other to create the design. It’s one part Simple Simon and one part Fancy Nancy.

And honestly? If you skip the drizzle altogether and serve it “Plain Jane” style, nobody will complain a bit.

PRINTABLE RECIPE CARD

Yield: 15 servings

Beautiful Rhubarb Poke Cake Recipe

rhubarb poke cake

This moist, delicious poke cake starts with a yellow cake mix, then is infused with a sweet-tangy rhubarb sauce. Smothered in whipped topping with an artful swirl of rhubarb sauce on top. The perfect summer dessert!

Prep Time 15 minutes
Cook Time 25 minutes
Additional Time 3 hours
Total Time 3 hours 40 minutes

Ingredients

Cake

  • 1 boxed yellow cake mix (or you can use a white or lemon cake mix)
  • 3 eggs
  • 1 cup water
  • 1/2 cup vegetable oil

Rhubarb Sauce

  • 1 small box strawberry jello (or raspberry jello)
  • 2 cups finely diced rhubarb
  • 1 cup sugar
  • 1 1/2 cups water

Topping

  • One small container whipped topping, thawed
  • 1/2 cup reserved rhubarb sauce

Instructions

Prepare Rhubarb Sauce

  1. Pour 1 cup of sugar over finely diced rhubarb and let it sit for an hour or more to draw out juice. You can do this in the saucepan you will use to prepare the topping.
  2. Add water and simmer on low/medium heat until rhubarb is completely tender.
  3. Stir in the jello and keep stirring until the jello is completely dissolved in the liquid. Set aside while the cake bakes. Reserve 1/2 cup of topping to decorate the top of the cake.

Prepare Cake

  1. Prepare the cake according to the package directions and bake at 350 degrees in a sprayed 9" x 13" cake pan for about 25 minutes or until a cake tester comes out clean, the top springs back when lightly touched, and the cake pulls back slightly from the edges of the pan. Don't underbake.
  2. While the cake is still hot, use the handle of a wooden spoon to poke large holes all over it. Pour the topping over the hot cake and use a rubber spatula to coax the topping into the holes.
  3. Refrigerate until the jello is set, at least two hours. The cake needs to be cool before adding whipped topping.
  4. Smooth a tub of defrosted whipped topping over the surface of the cake, clear to the edge of the pan.
  5. Drizzle four or five skinny lines of topping lengthwise on top of the cake. You may need to add a LITTLE bit of warm water and stir until it will drizzle from a measuring cup with a lip.
  6. Draw a table knife through the topping and rhubarb drizzle, first in one direction and then the other to form the nifty design! It's one part Simple Simon, one part Fancy Nancy.
  7. FEEL FREE TO SKIP THE DRIZZLE if you want!! It will be just as delicious as a "Plain Jane," I promise!

Notes

This cake needs to be refigerated but take it out a little bit before you serve it for the very best experience! It would make a great dessert for any of our American holidays! Go crazy and stud topping with blueberries and add some tiny American flags if you want to make it extra fancy!

Nutrition Information:

Yield:

15

Serving Size:

1

Amount Per Serving: Calories: 277Total Fat: 10gSaturated Fat: 2gTrans Fat: 0gUnsaturated Fat: 7gCholesterol: 37mgSodium: 316mgCarbohydrates: 45gFiber: 1gSugar: 30gProtein: 3g

FAQs

Can I use a different flavor of cake mix?

Absolutely! White, yellow, or lemon cake mix all work beautifully in this recipe. Lemon gives the cake a bright summery flavor, while white and yellow cake mixes let the rhubarb topping really shine.

What flavor of gelatin works best?

Strawberry is the classic choice, but cherry or raspberry gelatin is delicious too. Any red gelatin flavor pairs nicely with tart rhubarb and gives the cake that gorgeous, bright color.

Can I make rhubarb poke cake ahead of time?

Yes — in fact, it’s even better after it chills for several hours. This is a terrific make-ahead dessert for potlucks, cookouts, graduations, and summer gatherings.

Does this cake need to be refrigerated?

It does. Because of the whipped topping and fruit filling, the cake should be covered and refrigerated.

Can I freeze rhubarb poke cake?

You can, although the texture of the whipped topping may soften a little after thawing. For best results, freeze the cake before adding the topping, then thaw and decorate before serving.

This cake would be a great finale for a summer picnic! Serve it after the brats, beans, potato salad, and coleslaw pasta. Everyone will be patting their tummies and grinning from ear to ear!

Love the idea of poke cakes and summer cakes? Here are some of our very favorites!

❤️🤍💙 Festive Summer Poke Cake - A light, cool, and refreshing cake poked with two flavors of jello and frosted with whipped topping and sprinkles for a pretty Fourth of July holiday dessert!

🍫 Almond Joy Poke Cake - A delicious poke cake that starts with a cake mix and a pudding mix. All the flavors of an Almond Joy candy bar in a wonderfully moist cake, topped with toasted coconut and almonds.

🤎 Snickers Poke Cake - This is a quick and easy "poke" cake that starts with a basic chocolate cake mix, poked full of caramel topping. Top it with thick chocolate frosting and chopped peanuts for that total Snickers vibe!

🥤 Root Beer Float Cake - Here is a recipe for an easy, yummy root beer-flavored cake with thick root beer-flavored cream cheese frosting! It makes you feel like a kid!

If you enjoyed a post, I'd love it if you told me how it turned out or left a review or comment. It helps my little business, because YOU are exactly the kind of people I write for! ❤❤

Love, GB (Betty Streff)

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4 comments on “Beautiful Rhubarb Poke Cake — Summer In a 9x13 Pan”

    1. Oh good grief Gayle I am so thankful for you!!! I left the recipe card out!! Lame lame lame. The answer is 1 1/2 cups and its on the recipe card!!! Thank you thank you thank you!!

  1. Can you make this recipe the day before?
    Or can you make the cake/rhubarb the day before, then the day you are serving put cool whip topping on cake (warm leftover rhubarb for topping)?

    1. I'm not quite sure what you're asking but it sounds like you're wondering if you can bake the cake, NOT make it a poke cake, then serve the cake with whipped topping and rhubarb sauce. If so, sure. The cake made as the recipe indicates is great made the day ahead and if you want to skip the whipped topping and sauce untill you serve it, that would be fine too. If I have that wrong please holler back at me!!

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