Use .sort_by instead of .order

active_hash had an issue raised which seems to relate to the bug in
production where .order method breaks finder, returning the wrong record
for the given parameters

active-hash/active_hash#193

app/controllers/plants_controller.rb

@@ -14,7 +14,7 @@ def index
       end
     end
 
-    @plants = Plant.where(filter).order(week: :desc)
+    @plants = Plant.where(filter).sort_by(&:week).reverse
   end
 
   def show