Blackberry and blueberry crumb bars are easy to make and so full of flavor thanks to a layer of blackberries and blueberries.

Stack of four crumb bars on marble countertop with text overlay "blackberry & blueberry crumb bars."

IS IT SPRING YET?!?!!? For real. I am getting so stinking stir crazy. And a little bored. I’m meeting new friends though. Today at the library, I saw a mom that I saw at the mall play area just last week (I was just there yesterday too, for the record). We’re allllll going stir crazy and I’m getting so tired of the same ol’ routine:

Monday: Play area at the mall.

Tuesday: Library.

Wednesday: Play date at friends or other fun indoor location (yes, we have taken our children rollerskating. Yes, it is hysterical. Yes, E loves/hates it.)

Thursday: Shopping or errands.

Friday: Open gymnastics or other INDOOR activity.

Sounds fun right? No really, it actually does sound fun. And it is fun. Was fun. The first 4 weeks of winter or so. Now? I’m craving summmmmmer. Parks. Zoos. Splash pads. Even just a walk around the stinkin’ block. C’mon Michigan!!! Throw us a bone.

I’m sure you’ll all be happy when it finally gets warmer too because then maybe I’ll finally stop complaining about it.

In the meantime, I’ll bake. And I’ll throw berries in and pretend they are not from Mexico.

Closeup of crumb bar with stack of bars in background.

About these crumb bars

These blackberry blueberry crumb bars are so good — the chewy oats give them great texture. 

I could eat the filling with a spoon. Tons of crumb bar recipes use jam or jelly as a filling but it’s so easy to make the filling yourself with fresh blackberries and frozen blueberries (fresh would be great too…but…umm…yeah.).

These crumb bars are also flavored with plenty of lemon and lemon zest to freshen the whole thing up and then a little secret ingredient — cardamom! Cardamom adds an amazing subtle flavor that takes these crumb bars over the top. Enjoy!

Partial front view image of stacked crumb bars.

More yummy bars!

A pan of bars is so much quicker to bake than cookies. Try some of these yummy recipes:


Stack of 4 crumb bars on marble countertop.

Blackberry and Blueberry Crumb Bars

Yield: 20 servings
Prep Time: 20 minutes
Cook Time: 1 hour 5 minutes
Total Time: 1 hour 25 minutes

Blackberry and blueberry crumb bars are easy to make and so full of flavor thanks to a layer of blackberries and blueberries.


For the filling:

  • 1/4 cup sugar
  • 2 tablespoons cornstarch
  • 1 cup blueberries
  • 1 cup blackberries
  • 2 tablespoons fresh lemon juice
  • 1 teaspoon lemon zest
  • 3 tablespoons water

For the bars:

  • 2 cups oats (quick or old-fashioned (or use a mix of both)
  • 2 cups all-purpose flour
  • 1 1/4 cups light brown sugar, firmly packed
  • 1/2 teaspoon ground cardamom
  • 1 teaspoon lemon zest
  • 1/2 teaspoon salt
  • 2 tablespoons fresh lemon juice
  • 1 cup unsalted butter, cold and cut into small pieces


  1. Preheat oven to 325°F.
  2. In a small saucepan, mix together sugar and cornstarch. Add remaining filling ingredients (1 cup blueberries, 1 cup blackberries, 2 tablespoons lemon juice, 1 teaspoon lemon zest and 3 tablespoons water). Stir to combine. Bring to a simmer over medium heat and stir frequently. Reduce heat to medium low and continue to cook until thickened and berries are mostly broken down (10-15 minutes).
  3. Meanwhile, prepare dough for the bars. In a large mixing bowl, combine oats, flour, brown sugar, cardamom, 1 teaspoon lemon zest, and salt until well combined. Sprinkle mixture with 2 tablespoons fresh lemon juice. Add butter and use a pastry cutter or two forks or knives to cut in the butter pieces until the mixture is crumbly and there are no large chunks of butter remaining.
  4. Spray a 9×13-inch pan with nonstick cooking spray.
  5. Set aside 2 cups of crumb mixture. Pour the rest into the prepared pan and press down with fingers to form a uniform crust. Bake for 10 minutes or until set. Spread fruit filling evenly over crust. Sprinkle with reserved oat mixture and press down gently (be careful for the hot pan!).
  6. Bake for an additional 35-40 minutes or until golden brown.
  7. Cool completely before cutting into bars.


  • Lemon juice and zest needed for this recipe requires 2-3 lemons.
  • If desired, use all blueberries or all blackberries.
Nutrition Information:
Yield: 20 Serving Size: 1 bar
Amount Per Serving: Calories: 222Total Fat: 10gSaturated Fat: 6gTrans Fat: 0gUnsaturated Fat: 3gCholesterol: 24mgSodium: 58mgCarbohydrates: 32gFiber: 2gSugar: 15gProtein: 3g sometimes provides nutritional information, but these figures should be considered estimates, as they are not calculated by a registered dietitian. Please consult a medical professional for any specific nutrition, diet, or allergy advice.

Did you make this recipe?

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Verdict: Oh my goodness. I may have had one (or two) for breakfast.
Husband’s take: He likes them too — and I made him take them to work so I wouldn’t eat them all. Word is that people at his work are getting mad at me for sending them all my sweets. Anyone want to be my taste tester?
Changes I would make: None are necessary.
Difficulty: Easy.

Crumb bars on marble countertop.