diff --git a/liquidprompt b/liquidprompt
index 26021eb..51f90e0 100755
--- a/liquidprompt
+++ b/liquidprompt
@@ -788,16 +788,33 @@ _lp_git_branch_color()
 }
 
 
+_lp_upwards_find()
+{
+    while [[ $PWD != / ]] ; do
+        find "$PWD"/ -maxdepth 1 -name '$@' 2> /dev/null
+        cd ..
+    done
+}
+
 # MERCURIAL #
 
 # Get the branch name of the current directory
 _lp_hg_branch()
 {
     [[ "$LP_ENABLE_HG" != 1 ]] && return
+   
+    # First do a simple search to avoid having to invoke hg -- at least on my
+    # machine, the python startup causes a noticeable hitch when changing
+    # directories.
+    [[ -z $(_lp_upwards_find '.hg') ]]  && return
+
+    # We found an .hg folder, so we need to invoke hg and see if we're actually
+    # in a repository.
+    
     local branch
     branch="$(hg branch 2>/dev/null)"
-    [[ $? -eq 0 ]] && _lp_escape "$branch"
 
+    [[ $? -eq 0 ]] && _lp_escape "$branch"
 }
 
 # Set a color depending on the branch state:
@@ -1013,6 +1030,15 @@ _lp_fossil_branch_color()
 _lp_bzr_branch()
 {
     [[ "$LP_ENABLE_BZR" != 1 ]] && return
+
+    # First do a simple search to avoid having to invoke bzr -- at least on my
+    # machine, the python startup causes a noticeable hitch when changing
+    # directories.
+    [[ -z $(_lp_upwards_find '.bzr') ]]  && return
+
+    # We found an .bzr folder, so we need to invoke bzr and see if we're
+    # actually in a repository.
+
     local branch
     branch="$(bzr nick 2> /dev/null)"
     [[ $? -ne 0 ]] && return
@@ -1029,6 +1055,15 @@ _lp_bzr_branch()
 _lp_bzr_branch_color()
 {
     [[ "$LP_ENABLE_BZR" != 1 ]] && return
+
+    # First do a simple search to avoid having to invoke bzr -- at least on my
+    # machine, the python startup causes a noticeable hitch when changing
+    # directories.
+    [[ -z $(_lp_upwards_find '.bzr') ]]  && return
+
+    # We found an .bzr folder, so we need to invoke bzr and see if we're
+    # actually in a repository.
+
     local output
     output="$(bzr version-info --check-clean --custom --template='{branch_nick} {revno} {clean}' 2> /dev/null)"
     [[ $? -ne 0 ]] && return