Grapefruit Poppy Seed Cake

Glazed Grapefruit Poppy Seed Cake

Grapefruit Poppy Seed Cake…can’t you just taste it now? It’s packed to the gills with the essence of fresh grapefruit and positively loaded with poppy seeds.

Glazed Grapefruit Poppy Seed Cake

That’s white grapefruit, by the way, the most under appreciated citrus fruit. Those sugary red and pink varieties are fine, but my heart belongs to the ever so slightly bitter, puckeringly sour white fruit.

Especially when you bake it up in a cake — the flavor is subtle and sophisticated. I’ve used white grapefruit in lots of recipes on the blog, from my unusual GRAPEFRUIT BLOSSOM POT DE CREME, to my HOMEMADE WHITE GRAPEFRUIT VINEGAR. One of the simplest is my GRAPEFRUIT BRÛLÉE which takes the world’s healthiest breakfast ~ a half grapefruit ~ and gives it just a touch of decadence!

Just baked grapefruit poppy seed cake

It’s hard to keep track of all the layers of grapefruit in this poppy seed cake…it starts with fresh juice and zest blended into the batter, then, after baking, the still warm cake gets drenched with yet more juice, and finally the whole thing is topped off with a grapefruit glaze… just in case there were any doubts!

White Grapefruit and Poppy Seed Cake

That extra soaking with fresh grapefruit juice after it comes out of the oven gives this cake more citrus flavor than you could ever pack into it otherwise.

It seems to me that this technique has fallen out of popularity in recent years, we used to do it all the time with lemon and orange pound cakes…stabbing them with chopsticks and filling them to their limit with a thick syrup made by boiling down the fruit juice mixed with  sugar. If you love citrus like I do, it’s one of the few ways to really infuse citrus flavor into anything baked. You could make a grapefruit syrup for this cake, but I think it’s easier, and fresher tasting, to use the plain juice. You can poke holes all over the top to encourage the juice to sink in, or just pour it right down that lovely crack that opens up along the equator of the cake as it bakes.

Grapefruit Poppy Seed Cake batter

I know 3/4 of a cup sounds like an awful lot of poppy seeds, (and it is!) but they give flavor and crunch to the cake, and they create a unique texture as well. You can find inexpensive poppy seeds in bulk containers online at Amazon. But don’t try to do this with the teeny bottles the big name spice companies sell, it’ll put you in the poorhouse! Can you make this with fewer poppy seeds? Sure, it just won’t be as special.

Grapefruit and Poppy Seed Cake

And yes, in case you were wondering, poppy seeds can trigger a false-positive result on a drug test…but no, you can’t get ‘high’ by eating them…so just plan accordingly, and enjoy!

Super moist Grapefruit and Poppy Seed Cake

You are going to need about 2 grapefruits for this cake.

Just baked grapefruit poppy seed cake
4.43 from 7 votes

Grapefruit Poppy Seed Cake

Grapefruit Poppy Seed Cake...can't you just taste it now? It's packed to the gills with the essence of fresh grapefruit and positively loaded with poppy seeds.
Course Dessert
Cuisine American
Prep Time 15 minutes
Cook Time 50 minutes
Yield 16 servings
Author Sue Moran


  • 3/4 cup right poppy seeds
  • 1 cup buttermilk
  • zest of 2 grapefruits
  • 5 Tbsp fresh grapefruit juice
  • 1 cup 2 sticks unsalted butter, at room temperature
  • 1 cup sugar
  • 3 large eggs

dry ingredients

  • 2 3/4 cups all purpose flour
  • 1 tsp baking powder
  • 1 tsp baking soda
  • 1/8 tsp salt

for soaking

  • 1/2 cup fresh grapefruit juice


  • 1 1/2 cups confectioner's sugar
  • several Tbsp of fresh grapefruit juice


  • Set oven to 350F
  • Grease a standard bundt pan.
  • Put the buttermilk in a small bowl and add the poppy seeds, grapefruit juice, and zest. Stir to combine and set aside.
  • Cream the butter and sugar together until fluffy. Beat in the eggs, one at a time.
  • Whisk together the dry ingredients in a separate bowl.
  • Add the dry ingredients to the creamed butter mixture, alternating with the buttermilk mixture. Add about 1/3 of the flour, then 1/3 of the buttermilk, and continue until everything is well combined.
  • Spread the batter in the bundt pan. Smooth the top slightly to make sure it is even.
  • Bake for about 50 minutes, until the top is risen and golden, and a toothpick inserted in the center comes out without wet batter clinging to it.
  • Let the cake cool for about 10 to 15 minutes and then loosen the cake all the way around the pan and invert it onto a plate. If you have trouble removing it, rap the bottom of the pan sharply on a firm surface and try again.
  • Flip the cake back over so the risen side is up. Make little holes with a skewer all over the top and then spoon the fresh juice all over the top, letting the juice seep into the cake. Do this slowly so the juice has a chance to soak in.
  • When the cake is completely cool. pour the glaze over it, and enjoy.
The nutritional information for recipes on this site is provided as a courtesy and although tries to provide accurate nutritional information, these figures are only estimates.

more grapefruit poppy seed love …

Glazed Grapefruit Poppy Seed Muffins from Girl Versus Dough

Grapefruit Poppy Seed Vinaigrette from Cooking Light

Grapefruit Poppy Seed Bread from The Year in Food

Grapefruit Poppy Seed Doughnuts from Baker by Nature

Grapefruit Poppy Seed Bars from Epicurious


Don’t forget to pin this Grapefruit Poppy Seed Cake!

Grapefruit Poppy Seed Cake pin


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    Leave a Reply

    Please rate this recipe!

  • Reply
    Delwyn Wilkinson
    August 21, 2020 at 9:16 pm

    5 stars
    OMG, What an absolute Treat. Super Super delicious…..

  • Reply
    May 3, 2017 at 3:33 pm

    Looks heavenly but I’m wondering why you flip the cake back over so the risen side is up? That is unusual for Bundt cakes.

    • Reply
      May 3, 2017 at 3:37 pm

      I did that because I think the glaze sinks in better, but you can do it either way, Toesin.

  • Reply
    April 7, 2015 at 10:55 am

    5 stars
    I just made this over the weekend and it turned out lovely! It rose really well and was very moist. My glaze didn’t turn out as nice as yours in the photos, but the cake itself was delicious!

    • Reply
      April 7, 2015 at 11:00 am

      Glaze is so tricky, I often need to make it much thicker than I think so that it doesn’t disappear right into the cake!

  • Reply
    March 10, 2015 at 8:25 am

    Oh my gosh, this looks so good! I remember stopping on I-5 on our way from San Francisco to LA one time and picking up a bag of white grapefruit on the side of the road–it was the best grapefruit I ever ate!!!

  • Reply
    tina jeffers
    March 5, 2015 at 1:07 pm

    I love grapefruit and it’s so nice to have something so bright and fresh in the dead of winter. Can’t wait to try it!

  • Reply
    Jules @ WolfItDown
    March 1, 2015 at 9:53 am

    Ah! This sounds heavenly! I love grapefruit, and I have been wanting one of those cake tins SO bad! Cooks more evenly than the normal ones, no? 🙂 x

    PS I love the fresh recipes and the photos here 😀

  • Reply
    February 25, 2015 at 10:04 pm

    Gorgeous! Hubby can’t do grapefruit, so I’d have this all to myself. 🙂 Love all of the poppyseeds!

  • Reply
    Kitchen Belleicious
    February 25, 2015 at 7:32 pm

    usually its lemon with poppy seeds but I am loving that it is grapefruit and I can only imagine how wonderful this taste

  • Reply
    [email protected]+This+is+How+I+Cook
    February 25, 2015 at 3:30 pm

    You are on a citrus roll! Love the twist on this cake, Sue!

  • Reply
    February 25, 2015 at 3:03 pm

    Well, HEY NOW! I haven’t popped in in a good while and look what I find when I do! I see you’ve been busy! This cake is such a clever spin on that old chestnut of a lemon poppyseed cake! Clever and lovely! That firstphoto makes drew me right in on this post, Sue! Gorgeous and luscious!

    • Reply
      February 25, 2015 at 5:13 pm

      Thanks Susan, I love that phrase ‘an old chestnut’ — sometimes they’re the best recipes!!

  • Reply
    Nancy Buchanan
    February 25, 2015 at 12:40 pm

    It does my heart good to know I am not the only lover of yellow (as in flesh!) grapefruits – and in a poppy seed cake??? Sheer bliss! Seriously cannot wait to try this – love the tip about just using the juice to flavor the cake after it bakes – brilliant!!!

  • Reply
    [email protected]+Riffs
    February 25, 2015 at 10:19 am

    I love poppy seed cake. Never had it with grapefruit, though. Terrific idea — thanks.

  • Reply
    Donna Elick
    February 25, 2015 at 7:58 am

    Oh wow Sue! What a delicious twist on poppyseed cake. I am ever intrigued by the use of white grapefruit. I am a pink lover (for eating fresh) but can’t wait to try white in baked goods.

  • Reply
    February 25, 2015 at 6:34 am

    i do get so tired of lemon poppy seed this and lemon poppy seed that. it’s time a different kind of citrus teamed up with poppy seeds! this looks fabulous. 🙂

  • Reply
    Chris @ The Café Sucré Farine
    February 24, 2015 at 6:17 pm

    This one is calling my name, it looks beyond amazing Sue!

  • Reply
    [email protected]
    February 24, 2015 at 5:13 pm

    I love grapefruit but I would not have tried it in a cake like this for fear it would make it quite bitter (you see I love those white grapefruits from my garden too). I have made something like this with lemon. A good cup of tea is definitely in order with this little beauty.

  • Reply
    Pamela @ Brooklyn Farm Girl
    February 24, 2015 at 3:24 pm

    What a gorgeous cake! I love desserts with poppy seeds, so I will have to bake this soon!

  • Reply
    February 24, 2015 at 5:49 am

    Looks beautiful and tasty, Sue. Have been working my way through a cookbook my daughter gave me and one of the recipes is a kumquat poppy seed cake. Hoping I can still find some kumquats in the market, but doubt it…..might have to wait until next winter. 🙁

  • Reply
    Laura (Tutti Dolci)
    February 23, 2015 at 10:23 pm

    Oh yes I can taste this cake! I love all the poppy seeds and that glaze is luscious!

  • Reply
    February 23, 2015 at 9:55 pm

    Dear Susan, this cake looks beautiful and sounds like heaven to me! Pinned. xo, Catherine

    • Reply
      February 23, 2015 at 10:00 pm


  • Reply
    Barbara @ Barbara Bakes
    February 23, 2015 at 7:03 pm

    What a beautiful cake. Love the glaze.

  • Reply
    February 23, 2015 at 5:58 pm

    Whoa, does your cake look terrific! Nice idea to use grapefruit juice instead of the typical lemon 🙂

  • Reply
    February 23, 2015 at 1:54 pm

    I bet it is delicious!
    I am so happy to have found a whole lot of poppy seeds somewhere..they are getting scarcer and scarcer here.

  • Reply
    February 23, 2015 at 1:41 pm

    I agree with your comment of having a preference for white grapefruit. Except I would end your sentence with “especially in cocktails”. GREG

  • Reply
    Alice @ Hip Foodie Mom
    February 23, 2015 at 12:15 pm

    Sue, I’m all about citrus these days. . I LOVE this cake!!!! thanks for the tip on the poppy seeds!

    • Reply
      February 23, 2015 at 12:43 pm


  • Reply
    [email protected]'s+Recipes
    February 23, 2015 at 11:04 am

    That’s lots of poppy seeds! The cake looks super, Sue.

  • Reply
    February 23, 2015 at 10:18 am

    You know, I have never tried grapefruit in a cake recipe! This sound so good and bring on the poppy seeds, in my opinion. We just returned from a week in California where citrus trees were loaded with fruit and we ate our fair share. Great recipe!

    • Reply
      February 23, 2015 at 10:23 am

      Thanks Susan, the trees are loaded here, and what’s even better, the blossoms for the next crop are coming out and the scent is unreal.

  • Reply
    February 23, 2015 at 9:11 am

    Wow! What a beautiful cake! I cant wait to make it. I made your cardamom crumb cake this past weekend. Absolute heaven on an plate! I so enjoy visiting here!

    • Reply
      February 23, 2015 at 9:37 am

      Thanks so much, I love good feedback 😉 This cake is wonderful, but after my brownies earlier this week, I had to give most of this one away or I’d be in serious trouble…

  • Reply
    Jessica | A Happy Food Dance
    February 23, 2015 at 8:20 am

    Love the extra soaking with grapefruit juice, I bet that give the cake such an intense citrus flavor! Beautiful photos too!

    • Reply
      February 23, 2015 at 9:37 am

      It’s a nice change from lemon!

  • Reply
    Stephanie @ Girl Versus Dough
    February 23, 2015 at 8:11 am

    This cake looks to die for! The more poppy seeds, the better, I think. 🙂

  • Reply
    Tricia @ Saving room for dessert
    February 23, 2015 at 7:07 am

    Well that is one gorgeous cake! I adore grapefruit and have been devouring them lately. They are so juicy! Give me a cup of tea and a slice of this cake – yum!

  • Reply
    Jennifer @ Seasons and Suppers
    February 23, 2015 at 5:33 am

    So lovely! I am so loving all the citrus goodies this time of year 🙂

  • Reply
    Jennifer Farley
    February 23, 2015 at 5:23 am

    I just love grapefruit in baked goods. This looks amazing.

    • Reply
      February 23, 2015 at 7:47 am

      Your grapefruit curd ice cream is my hero…

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