diff --git a/crates/ra_cargo_watch/src/lib.rs b/crates/ra_cargo_watch/src/lib.rs
index 94b9c03d0c1..1a6926db3b5 100644
--- a/crates/ra_cargo_watch/src/lib.rs
+++ b/crates/ra_cargo_watch/src/lib.rs
@@ -254,6 +254,7 @@ impl WatchThread {
     fn new(options: &CheckOptions, workspace_root: &PathBuf) -> WatchThread {
         let mut args: Vec<String> = vec![
             options.command.clone(),
+            "--workspace".to_string(),
             "--message-format=json".to_string(),
             "--manifest-path".to_string(),
             format!("{}/Cargo.toml", workspace_root.to_string_lossy()),