diff --git a/backend/src/utils/validation.js b/backend/src/utils/validation.js
index 05061ff..700ed1a 100644
--- a/backend/src/utils/validation.js
+++ b/backend/src/utils/validation.js
@@ -76,11 +76,11 @@ const productRateSchema = Joi.object({
 });
 
 const userProductSchema = Joi.object({
-  productId: Joi.number().integer().positive(),
-  customName: Joi.string().max(255),
-  customRateAmount: Joi.number().positive(),
-  customRateUnit: Joi.string().max(50),
-  notes: Joi.string()
+  productId: Joi.number().integer().positive().allow(null).optional(),
+  customName: Joi.string().max(255).allow(null).optional(),
+  customRateAmount: Joi.number().positive().allow(null).optional(),
+  customRateUnit: Joi.string().max(50).allow(null).optional(),
+  notes: Joi.string().allow(null, '').optional()
 });
 
 // Application validation schemas
diff --git a/frontend/src/pages/Products/Products.js b/frontend/src/pages/Products/Products.js
index 8482099..3b1e8ba 100644
--- a/frontend/src/pages/Products/Products.js
+++ b/frontend/src/pages/Products/Products.js
@@ -350,6 +350,10 @@ const CreateProductModal = ({ onSubmit, onCancel, sharedProducts, categories })
   const [formData, setFormData] = useState({
     productId: '',
     customName: '',
+    categoryId: '',
+    productType: 'granular',
+    brand: '',
+    activeIngredients: '',
     customRateAmount: '',
     customRateUnit: 'lbs/1000 sq ft',
     notes: ''
@@ -363,6 +367,12 @@ const CreateProductModal = ({ onSubmit, onCancel, sharedProducts, categories })
       return;
     }
 
+    // If creating a completely custom product (no base product), require more fields
+    if (!formData.productId && (!formData.categoryId || !formData.productType)) {
+      toast.error('Please select a category and product type for custom products');
+      return;
+    }
+
     const submitData = {
       productId: formData.productId ? parseInt(formData.productId) : null,
       customName: formData.customName || null,
@@ -413,6 +423,63 @@ const CreateProductModal = ({ onSubmit, onCancel, sharedProducts, categories })
             </p>
           </div>
 
+          {/* Show additional fields when creating completely custom product */}
+          {!formData.productId && (
+            <>
+              <div className="grid grid-cols-2 gap-4">
+                <div>
+                  <label className="label">Category *</label>
+                  <select
+                    className="input"
+                    value={formData.categoryId}
+                    onChange={(e) => setFormData({ ...formData, categoryId: e.target.value })}
+                    required={!formData.productId}
+                  >
+                    <option value="">Select category...</option>
+                    {categories.map((category) => (
+                      <option key={category.id} value={category.id}>
+                        {category.name}
+                      </option>
+                    ))}
+                  </select>
+                </div>
+                <div>
+                  <label className="label">Product Type *</label>
+                  <select
+                    className="input"
+                    value={formData.productType}
+                    onChange={(e) => setFormData({ ...formData, productType: e.target.value })}
+                  >
+                    <option value="granular">Granular</option>
+                    <option value="liquid">Liquid</option>
+                  </select>
+                </div>
+              </div>
+
+              <div>
+                <label className="label">Brand</label>
+                <input
+                  type="text"
+                  className="input"
+                  value={formData.brand}
+                  onChange={(e) => setFormData({ ...formData, brand: e.target.value })}
+                  placeholder="e.g., Scotts, Syngenta, Custom Mix"
+                />
+              </div>
+
+              <div>
+                <label className="label">Active Ingredients</label>
+                <input
+                  type="text"
+                  className="input"
+                  value={formData.activeIngredients}
+                  onChange={(e) => setFormData({ ...formData, activeIngredients: e.target.value })}
+                  placeholder="e.g., 2,4-D 25%, Nitrogen 24%, Iron 2%"
+                />
+              </div>
+            </>
+          )}
+
           <div className="grid grid-cols-2 gap-4">
             <div>
               <label className="label">Application Rate</label>