diff --git a/default_settings.txt b/default_settings.txt
index 9f8fc3c..18770db 100644
--- a/default_settings.txt
+++ b/default_settings.txt
@@ -130,6 +130,9 @@ moretrees.dates_item_drop_ichance	= 10 		-- inverse probability of ripe dates dr
 moretrees.sapling_interval		= 100
 moretrees.sapling_chance		= 5
 
+-- Enable this only if you have used an old moretrees version which was using biome_lib and when you notice large areas with ongen saplings that don't grow
+moretrees.grow_legacy_saplings	= false
+
 -- If this variable is set to true, drop leaves out as entities during leaf
 -- decay, rather than just disappearing them.
 
diff --git a/init.lua b/init.lua
index 621814a..63e6452 100644
--- a/init.lua
+++ b/init.lua
@@ -383,4 +383,17 @@ function moretrees.grow_fir_snow(pos)
 	minetest.spawn_tree(pos,moretrees.fir_model)
 end
 
+if moretrees.grow_legacy_saplings then
+	minetest.register_lbm({
+		name = "moretrees:grow_ongen_saplings",
+		label = "Grow legacy ongen saplings",
+		nodenames = { "group:moretrees_ongen" },
+		run_at_every_load = false,
+		action = function(pos)
+			minetest.log("info", "[moretrees] Starting growth timer for legacy ongen sapling at "..minetest.pos_to_string(pos, 0))
+			minetest.get_node_timer(pos):start(2)
+		end
+	})
+end
+
 minetest.log("info", "[moretrees] Loading done")
diff --git a/settings.lua b/settings.lua
index 1eca07b..f53cd88 100644
--- a/settings.lua
+++ b/settings.lua
@@ -74,6 +74,9 @@ moretrees.dates_item_drop_ichance	= tonumber(stg:get("moretrees.dates_item_drop_
 moretrees.sapling_interval		= 100
 moretrees.sapling_chance		= 5
 
+-- Enable this only if you have used an old moretrees version which was using biome_lib and when you notice large areas with ongen saplings that don't grow
+moretrees.grow_legacy_saplings	= stg:get_bool("moretrees.grow_legacy_saplings", false)
+
 -- If this variable is set to true, drop leaves out as entities during leaf
 -- decay, rather than just disappearing them.
 moretrees.decay_leaves_as_items = stg:get_bool("moretrees.decay_leaves_as_items", false)