diff --git a/src/components/Temple.tsx b/src/components/Temple.tsx
index 10381f2..8c00ad7 100644
--- a/src/components/Temple.tsx
+++ b/src/components/Temple.tsx
@@ -115,6 +115,7 @@ const TempleComponent: React.FC = () => {
     pray,
     piety,
     stamina,
+    milestones,
   } = useGameStore()
 
   const handlePurchase = (upgradeId: string) => {
@@ -136,44 +137,13 @@ const TempleComponent: React.FC = () => {
     }
 
     // Check if can afford
-    if (!canAffordUpgrade(upgrade.cost)) {
-      return false
-    }
-
-    // Check requirements
-    if (
-      upgrade.id === 'aqueous_vigor_2' &&
-      !purchasedUpgrades.includes('aqueous_vigor_1')
-    ) {
-      return false
-    }
-
-    if (
-      upgrade.id === 'aqua_diffundere_2' &&
-      !purchasedUpgrades.includes('aqua_diffundere_1')
-    ) {
-      return false
-    }
-
-    return true
+    return canAffordUpgrade(upgrade.cost)
   }
 
   const getUpgradeStatus = (upgrade: Upgrade) => {
     if (purchasedUpgrades.includes(upgrade.id)) {
       return 'Purchased'
     }
-    if (
-      upgrade.id === 'aqueous_vigor_2' &&
-      !purchasedUpgrades.includes('aqueous_vigor_1')
-    ) {
-      return 'Requires Aqueous Vigor I'
-    }
-    if (
-      upgrade.id === 'aqua_diffundere_2' &&
-      !purchasedUpgrades.includes('aqua_diffundere_1')
-    ) {
-      return 'Requires Aqua Diffundere I'
-    }
     if (!canAffordUpgrade(upgrade.cost)) {
       return 'Cannot Afford'
     }
@@ -193,35 +163,37 @@ const TempleComponent: React.FC = () => {
       </PrayerSection>
 
       <UpgradesGrid>
-        {Object.values(UPGRADES).map((upgrade) => {
-          const isPurchased = purchasedUpgrades.includes(upgrade.id)
-          const canPurchase = canPurchaseUpgrade(upgrade)
-          const status = getUpgradeStatus(upgrade)
+        {Object.values(UPGRADES)
+          .filter(upgrade => !upgrade.isAvailable || upgrade.isAvailable({ purchasedUpgrades, milestones }))
+          .map((upgrade) => {
+            const isPurchased = purchasedUpgrades.includes(upgrade.id)
+            const canPurchase = canPurchaseUpgrade(upgrade)
+            const status = getUpgradeStatus(upgrade)
 
-          return (
-            <UpgradeCard key={upgrade.id} purchased={isPurchased}>
-              <UpgradeName>{upgrade.name}</UpgradeName>
-              <UpgradeDescription>{upgrade.description}</UpgradeDescription>
-              <UpgradeCost>
-                <span>Cost:</span>
-                {upgrade.cost.map((cost, index) => (
-                  <CostItem key={index}>
-                    <span>
-                      {cost.amount} {cost.itemId}
-                    </span>
-                    <span>(You have: {inventory[cost.itemId] || 0})</span>
-                  </CostItem>
-                ))}
-              </UpgradeCost>
-              <PurchaseButton
-                onClick={() => handlePurchase(upgrade.id)}
-                disabled={!canPurchase}
-              >
-                {status}
-              </PurchaseButton>
-            </UpgradeCard>
-          )
-        })}
+            return (
+              <UpgradeCard key={upgrade.id} purchased={isPurchased}>
+                <UpgradeName>{upgrade.name}</UpgradeName>
+                <UpgradeDescription>{upgrade.description}</UpgradeDescription>
+                <UpgradeCost>
+                  <span>Cost:</span>
+                  {upgrade.cost.map((cost, index) => (
+                    <CostItem key={index}>
+                      <span>
+                        {cost.amount} {cost.itemId}
+                      </span>
+                      <span>(You have: {inventory[cost.itemId] || 0})</span>
+                    </CostItem>
+                  ))}
+                </UpgradeCost>
+                <PurchaseButton
+                  onClick={() => handlePurchase(upgrade.id)}
+                  disabled={!canPurchase}
+                >
+                  {status}
+                </PurchaseButton>
+              </UpgradeCard>
+            )
+          })}
       </UpgradesGrid>
     </TempleContainer>
   )
diff --git a/src/constants/index.ts b/src/constants/index.ts
index 244aabd..fa226d0 100644
--- a/src/constants/index.ts
+++ b/src/constants/index.ts
@@ -17,8 +17,8 @@ export const CROPS: CropDefinitions = {
   celery: {
     id: 'celery',
     name: 'Celery',
-    growthTicks: 36,
-    waterPerTick: 1 / 20,
+    growthTicks: 10,
+    waterPerTick: 1 / 5,
     yield: 1,
     yieldType: 'celery',
     fertilityDepletion: 0.1,
@@ -65,6 +65,50 @@ export const INITIAL_INVENTORY = {
 }
 
 export const UPGRADES: Record<string, Upgrade> = {
+  stamina_1: {
+    id: 'stamina_1',
+    name: 'Stamina I',
+    description: 'Increases maximum stamina by 5',
+    cost: [
+      {
+        itemId: 'celery',
+        amount: 20,
+      },
+    ],
+  },
+  stamina_2: {
+    id: 'stamina_2',
+    name: 'Stamina II',
+    description: 'Increases maximum stamina by 8',
+    cost: [
+      {
+        itemId: 'corn',
+        amount: 20,
+      },
+    ],
+  },
+  stamina_3: {
+    id: 'stamina_3',
+    name: 'Stamina III',
+    description: 'Increases maximum stamina by 12',
+    cost: [
+      {
+        itemId: 'olives',
+        amount: 100,
+      },
+    ],
+  },
+  stamina_4: {
+    id: 'stamina_4',
+    name: 'Stamina IV',
+    description: 'Increases maximum stamina by 15',
+    cost: [
+      {
+        itemId: 'grapes',
+        amount: 100,
+      },
+    ],
+  },
   aqueous_vigor_1: {
     id: 'aqueous_vigor_1',
     name: 'Aqueous Vigor I',
diff --git a/src/store/useGameStore.ts b/src/store/useGameStore.ts
index 32f4b4b..5c8002b 100644
--- a/src/store/useGameStore.ts
+++ b/src/store/useGameStore.ts
@@ -505,6 +505,21 @@ export const useGameStore = create<
           })
           state.purchasedUpgrades.push(upgradeId)
           addConsoleMessage(state, `Purchased upgrade: ${upgrade.name}`)
+
+          // Handle stamina upgrades
+          if (upgradeId === 'stamina_1') {
+            state.maxStamina += 5
+            state.stamina = Math.min(state.maxStamina, state.stamina + 5)
+          } else if (upgradeId === 'stamina_2') {
+            state.maxStamina += 8
+            state.stamina = Math.min(state.maxStamina, state.stamina + 8)
+          } else if (upgradeId === 'stamina_3') {
+            state.maxStamina += 12
+            state.stamina = Math.min(state.maxStamina, state.stamina + 12)
+          } else if (upgradeId === 'stamina_4') {
+            state.maxStamina += 15
+            state.stamina = Math.min(state.maxStamina, state.stamina + 15)
+          }
         }),
       )
     },
diff --git a/src/types/index.ts b/src/types/index.ts
index 5841773..25c01b0 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -48,6 +48,7 @@ export interface Upgrade {
   name: string
   description: string
   cost: UpgradeCost[]
+  isAvailable?: (state: Pick<GameState, 'purchasedUpgrades' | 'milestones'>) => boolean
 }
 
 export interface Recipe {