diff --git a/src/blockchain.rs b/src/blockchain.rs
index 2610407ac..757e51c59 100644
--- a/src/blockchain.rs
+++ b/src/blockchain.rs
@@ -785,8 +785,9 @@ mod tests {
 		}
 		assert!(bc.cache_size().blocks > 1024 * 1024);
 
-		bc.collect_garbage(true);
-
+		for _ in 0..2 {
+			bc.collect_garbage(true);
+		}
 		assert!(bc.cache_size().blocks < 1024 * 1024);
 	}