diff -r f6f6db47bd98 src/script/api/ai_changelog.hpp
--- a/src/script/api/ai_changelog.hpp	Mon Oct 28 11:09:02 2013 +0000
+++ b/src/script/api/ai_changelog.hpp	Mon Oct 28 12:29:28 2013 +0100
@@ -23,6 +23,7 @@
  * \li AIStation::HasCargoRating
  * \li AITile::GetTerrainType
  * \li AITown::FoundTown
+ * \li AITown::TOWN_GROWTH_NONE
  *
  * Other changes:
  * \li AIStation::GetCargoRating does return -1 for cargo-station combinations that
diff -r f6f6db47bd98 src/script/api/game_changelog.hpp
--- a/src/script/api/game_changelog.hpp	Mon Oct 28 11:09:02 2013 +0000
+++ b/src/script/api/game_changelog.hpp	Mon Oct 28 12:29:28 2013 +0100
@@ -30,6 +30,8 @@
  * \li GSTile::GetTerrainType
  * \li GSTown::FoundTown
  * \li GSTown::SetName
+ * \li GSTown::TOWN_GROWTH_NONE
+ * \li GSTown::TOWN_GROWTH_NORMAL
  *
  * Other changes:
  * \li GSGoal::New can now create up to 64000 concurrent goals. The old limit was 256 goals.
diff -r f6f6db47bd98 src/script/api/script_town.cpp
--- a/src/script/api/script_town.cpp	Mon Oct 28 11:09:02 2013 +0000
+++ b/src/script/api/script_town.cpp	Mon Oct 28 12:29:28 2013 +0100
@@ -154,12 +154,25 @@
 	}
 }
 
-/* static */ bool ScriptTown::SetGrowthRate(TownID town_id, uint16 days_between_town_growth)
+/* static */ bool ScriptTown::SetGrowthRate(TownID town_id, uint32 days_between_town_growth)
 {
-	days_between_town_growth = days_between_town_growth * DAY_TICKS / TOWN_GROWTH_TICKS;
+	EnforcePrecondition(false, IsValidTown(town_id));
 
-	EnforcePrecondition(false, IsValidTown(town_id));
-	EnforcePrecondition(false, (days_between_town_growth & TOWN_GROW_RATE_CUSTOM) == 0);
+	switch (days_between_town_growth) {
+		case TOWN_GROWTH_NORMAL:
+			days_between_town_growth = 0;
+			break;
+
+		case TOWN_GROWTH_NONE:
+			days_between_town_growth = TOWN_GROW_RATE_CUSTOM_NONE;
+			break;
+
+		default:
+			days_between_town_growth = days_between_town_growth * DAY_TICKS / TOWN_GROWTH_TICKS;
+			EnforcePrecondition(false, days_between_town_growth < TOWN_GROW_RATE_CUSTOM);
+			if (days_between_town_growth == 0) days_between_town_growth = 1;
+			break;
+	}
 
 	return ScriptObject::DoCommand(::Town::Get(town_id)->xy, town_id, days_between_town_growth, CMD_TOWN_GROWTH_RATE);
 }
@@ -170,6 +183,8 @@
 
 	const Town *t = ::Town::Get(town_id);
 
+	if (t->growth_rate == TOWN_GROW_RATE_CUSTOM_NONE) return TOWN_GROWTH_NONE;
+
 	return ((t->growth_rate & ~TOWN_GROW_RATE_CUSTOM) * TOWN_GROWTH_TICKS + DAY_TICKS) / DAY_TICKS;
 }
 
diff -r f6f6db47bd98 src/script/api/script_town.hpp
--- a/src/script/api/script_town.hpp	Mon Oct 28 11:09:02 2013 +0000
+++ b/src/script/api/script_town.hpp	Mon Oct 28 12:29:28 2013 +0100
@@ -117,6 +117,14 @@
 	};
 
 	/**
+	 * Special values for SetGrowthRate.
+	 */
+	enum TownGrowth {
+		TOWN_GROWTH_NONE   = 0xFFFF,  ///< Town does not grow at all. 
+		TOWN_GROWTH_NORMAL = 0x10000, ///< Use default town growth algorithm instead of custom growth rate.
+	};
+
+	/**
 	 * Gets the number of towns.
 	 * @return The number of towns.
 	 */
@@ -249,20 +257,20 @@
 	/**
 	 * Set the amount of days between town growth.
 	 * @param town_id The index of the town.
-	 * @param days_between_town_growth The amount of days between town growth.
+	 * @param days_between_town_growth The amount of days between town growth, or TOWN_GROWTH_NONE or TOWN_GROWTH_NORMAL.
 	 * @pre IsValidTown(town_id).
 	 * @return True if the action succeeded.
 	 * @note Even when setting a growth rate, towns only grow when the conditions for growth (SetCargoCoal) are met,
 	 *       and the game settings (economy.town_growth_rate) allow town growth at all.
 	 * @api -ai
 	 */
-	static bool SetGrowthRate(TownID town_id, uint16 days_between_town_growth);
+	static bool SetGrowthRate(TownID town_id, uint32 days_between_town_growth);
 
 	/**
 	 * Get the amount of days between town growth.
 	 * @param town_id The index of the town.
 	 * @pre IsValidTown(town_id).
-	 * @return Amount of days between town growth.
+	 * @return Amount of days between town growth, or TOWN_GROWTH_NONE.
 	 * @note This function does not indicate when it will grow next. It only tells you the time between growths.
 	 */
 	static int32 GetGrowthRate(TownID town_id);
diff -r f6f6db47bd98 src/town.h
--- a/src/town.h	Mon Oct 28 11:09:02 2013 +0000
+++ b/src/town.h	Mon Oct 28 12:29:28 2013 +0100
@@ -35,7 +35,8 @@
 
 static const uint TOWN_GROWTH_WINTER = 0xFFFFFFFE; ///< The town only needs this cargo in the winter (any amount)
 static const uint TOWN_GROWTH_DESERT = 0xFFFFFFFF; ///< The town needs the cargo for growth when on desert (any amount)
-static const uint16 TOWN_GROW_RATE_CUSTOM = 0x8000; ///< If this mask is applied to Town::grow_counter, the grow_counter will not be calculated by the system (but assumed to be set by scripts)
+static const uint16 TOWN_GROW_RATE_CUSTOM      = 0x8000; ///< If this mask is applied to Town::growth_rate, the grow_counter will not be calculated by the system (but assumed to be set by scripts)
+static const uint16 TOWN_GROW_RATE_CUSTOM_NONE = 0xFFFF; ///< Special value for Town::growth_rate to disable town growth.
 
 typedef Pool<Town, TownID, 64, 64000> TownPool;
 extern TownPool _town_pool;
diff -r f6f6db47bd98 src/town_cmd.cpp
--- a/src/town_cmd.cpp	Mon Oct 28 11:09:02 2013 +0000
+++ b/src/town_cmd.cpp	Mon Oct 28 12:29:28 2013 +0100
@@ -2513,14 +2513,14 @@
  * @param tile Unused.
  * @param flags Type of operation.
  * @param p1 Town ID to cargo game of.
- * @param p2 Amount of days between growth.
+ * @param p2 Amount of days between growth, or TOWN_GROW_RATE_CUSTOM_NONE, or 0 to reset custom growth rate.
  * @param text Unused.
  * @return Empty cost or an error.
  */
 CommandCost CmdTownGrowthRate(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	if (_current_company != OWNER_DEITY) return CMD_ERROR;
-	if ((p2 & TOWN_GROW_RATE_CUSTOM) != 0) return CMD_ERROR;
+	if ((p2 & TOWN_GROW_RATE_CUSTOM) != 0 && p2 != TOWN_GROW_RATE_CUSTOM_NONE) return CMD_ERROR;
 	if (GB(p2, 16, 16) != 0) return CMD_ERROR;
 
 	Town *t = Town::GetIfValid(p1);
@@ -2813,11 +2813,12 @@
 	if (flags & DC_EXEC) {
 		/* Build next tick */
 		t->grow_counter = 1;
-		/* If we were not already growing */
-		SetBit(t->flags, TOWN_IS_GROWING);
 		/* And grow for 3 months */
 		t->fund_buildings_months = 3;
 
+		/* Enable growth (also checking GameScript's opinion */
+		UpdateTownGrowRate(t);
+
 		SetWindowDirty(WC_TOWN_VIEW, t->index);
 	}
 	return CommandCost();
@@ -3035,7 +3036,7 @@
 	}
 
 	if ((t->growth_rate & TOWN_GROW_RATE_CUSTOM) != 0) {
-		SetBit(t->flags, TOWN_IS_GROWING);
+		if (t->growth_rate != TOWN_GROW_RATE_CUSTOM_NONE) SetBit(t->flags, TOWN_IS_GROWING);
 		SetWindowDirty(WC_TOWN_VIEW, t->index);
 		return;
 	}