diff --git a/src/wp-includes/class-wp-block-patterns-registry.php b/src/wp-includes/class-wp-block-patterns-registry.php
index e516277e42dde..08523cddcd397 100644
--- a/src/wp-includes/class-wp-block-patterns-registry.php
+++ b/src/wp-includes/class-wp-block-patterns-registry.php
@@ -112,7 +112,10 @@ public function register( $pattern_name, $pattern_properties ) {
 
 		$pattern = array_merge(
 			$pattern_properties,
-			array( 'name' => $pattern_name )
+			array(
+				'name'   => $pattern_name,
+				'parsed' => false,
+			)
 		);
 
 		$this->registered_patterns[ $pattern_name ] = $pattern;
@@ -190,8 +193,12 @@ public function get_registered( $pattern_name ) {
 			return null;
 		}
 
-		$pattern            = $this->registered_patterns[ $pattern_name ];
-		$pattern['content'] = $this->prepare_content( $pattern, get_hooked_blocks() );
+		$pattern = $this->registered_patterns[ $pattern_name ];
+		if ( ! $pattern['parsed'] ) {
+			$pattern['content']                         = $this->prepare_content( $pattern, get_hooked_blocks() );
+			$pattern['parsed']                          = true;
+			$this->registered_patterns[ $pattern_name ] = $pattern;
+		}
 
 		return $pattern;
 	}
@@ -206,16 +213,27 @@ public function get_registered( $pattern_name ) {
 	 *                 and per style.
 	 */
 	public function get_all_registered( $outside_init_only = false ) {
-		$patterns      = array_values(
-			$outside_init_only
+		$patterns = $outside_init_only
 				? $this->registered_patterns_outside_init
-				: $this->registered_patterns
-		);
+				: $this->registered_patterns;
+
 		$hooked_blocks = get_hooked_blocks();
-		foreach ( $patterns as $index => $pattern ) {
-			$patterns[ $index ]['content'] = $this->prepare_content( $pattern, $hooked_blocks );
+
+		foreach ( $patterns as $pattern_name => $pattern ) {
+			if ( ! $pattern['parsed'] ) {
+				$pattern['content']        = $this->prepare_content( $pattern, $hooked_blocks );
+				$pattern['parsed']         = true;
+				$patterns[ $pattern_name ] = $pattern;
+			}
 		}
-		return $patterns;
+
+		if ( $outside_init_only ) {
+			$this->registered_patterns_outside_init = $patterns;
+		} else {
+			$this->registered_patterns = $patterns;
+		}
+
+		return array_values( $patterns );
 	}
 
 	/**
diff --git a/tests/phpunit/tests/blocks/wpBlockPatternsRegistry.php b/tests/phpunit/tests/blocks/wpBlockPatternsRegistry.php
index 61298d1b164af..d10f3b64ec811 100644
--- a/tests/phpunit/tests/blocks/wpBlockPatternsRegistry.php
+++ b/tests/phpunit/tests/blocks/wpBlockPatternsRegistry.php
@@ -244,9 +244,12 @@ public function test_get_all_registered() {
 		);
 		$this->registry->register( 'test/three', $pattern_three );
 
-		$pattern_one['name']   = 'test/one';
-		$pattern_two['name']   = 'test/two';
-		$pattern_three['name'] = 'test/three';
+		$pattern_one['name']     = 'test/one';
+		$pattern_one['parsed']   = true;
+		$pattern_two['name']     = 'test/two';
+		$pattern_two['parsed']   = true;
+		$pattern_three['name']   = 'test/three';
+		$pattern_three['parsed'] = true;
 
 		$expected = array(
 			$pattern_one,
@@ -276,6 +279,7 @@ public function test_get_registered_rejects_unknown_pattern_name() {
 		$pattern_two = array(
 			'title'   => 'Pattern Two',
 			'content' => '<!-- wp:paragraph --><p>Two</p><!-- /wp:paragraph -->',
+			'parsed'  => true,
 		);
 		$this->registry->register( 'test/two', $pattern_two );
 
@@ -310,7 +314,8 @@ public function test_get_registered() {
 		);
 		$this->registry->register( 'test/three', $pattern_three );
 
-		$pattern_two['name'] = 'test/two';
+		$pattern_two['name']   = 'test/two';
+		$pattern_two['parsed'] = true;
 
 		$pattern = $this->registry->get_registered( 'test/two' );
 		$this->assertSame( $pattern_two, $pattern );
@@ -376,9 +381,12 @@ public function test_get_all_registered_includes_hooked_blocks() {
 		$this->registry->register( 'test/three', $pattern_three );
 
 		$pattern_one['name']       = 'test/one';
+		$pattern_one['parsed']     = true;
 		$pattern_two['name']       = 'test/two';
 		$pattern_two['content']   .= '<!-- wp:tests/my-block /-->';
+		$pattern_two['parsed']     = true;
 		$pattern_three['name']     = 'test/three';
+		$pattern_three['parsed']   = true;
 		$pattern_three['content'] .= '<!-- wp:tests/my-block /-->';
 
 		$expected = array(
@@ -445,6 +453,7 @@ public function test_get_registered_includes_hooked_blocks() {
 		$this->registry->register( 'test/two', $pattern_two );
 
 		$pattern_one['name']    = 'test/one';
+		$pattern_one['parsed']  = true;
 		$pattern_one['content'] = '<!-- wp:tests/my-block /-->' . $pattern_one['content'];
 
 		$pattern = $this->registry->get_registered( 'test/one' );