diff --git a/lib/rails_admin/config/fields/types/action_text.rb b/lib/rails_admin/config/fields/types/action_text.rb
index 276308f287..221ac80c32 100644
--- a/lib/rails_admin/config/fields/types/action_text.rb
+++ b/lib/rails_admin/config/fields/types/action_text.rb
@@ -1,11 +1,10 @@
-require 'rails_admin/config/fields/base'
 require 'rails_admin/config/fields/types/text'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class ActionText < RailsAdmin::Config::Fields::Types::Text
+        class ActionText < Text
           # Register field type for the type loader
           RailsAdmin::Config::Fields::Types.register(self)
 
diff --git a/lib/rails_admin/config/fields/types/ck_editor.rb b/lib/rails_admin/config/fields/types/ck_editor.rb
index 170bba4c17..f1f4f439bd 100644
--- a/lib/rails_admin/config/fields/types/ck_editor.rb
+++ b/lib/rails_admin/config/fields/types/ck_editor.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/text'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class CKEditor < RailsAdmin::Config::Fields::Types::Text
+        class CKEditor < Text
           # Register field type for the type loader
           RailsAdmin::Config::Fields::Types.register(self)
 
diff --git a/lib/rails_admin/config/fields/types/code_mirror.rb b/lib/rails_admin/config/fields/types/code_mirror.rb
index e1c66b5b45..0d45a16ae7 100644
--- a/lib/rails_admin/config/fields/types/code_mirror.rb
+++ b/lib/rails_admin/config/fields/types/code_mirror.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/text'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class CodeMirror < RailsAdmin::Config::Fields::Types::Text
+        class CodeMirror < Text
           # Register field type for the type loader
           RailsAdmin::Config::Fields::Types.register(self)
 
diff --git a/lib/rails_admin/config/fields/types/color.rb b/lib/rails_admin/config/fields/types/color.rb
index c048331403..554d2acbcc 100644
--- a/lib/rails_admin/config/fields/types/color.rb
+++ b/lib/rails_admin/config/fields/types/color.rb
@@ -1,19 +1,12 @@
-require 'rails_admin/config/fields/base'
-require 'rails_admin/config/fields/types/string'
+require 'rails_admin/config/fields/types/string_like'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class Color < RailsAdmin::Config::Fields::Types::String
+        class Color < StringLike
           RailsAdmin::Config::Fields::Types.register(self)
 
-          register_instance_option :html_attributes do
-            {
-              required: required?,
-            }
-          end
-
           register_instance_option :pretty_value do
             bindings[:view].content_tag :strong, (value.presence || ' - '), style: "color: #{color}"
           end
diff --git a/lib/rails_admin/config/fields/types/froala.rb b/lib/rails_admin/config/fields/types/froala.rb
index bce6530b1c..a88cc78013 100644
--- a/lib/rails_admin/config/fields/types/froala.rb
+++ b/lib/rails_admin/config/fields/types/froala.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/text'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class Froala < RailsAdmin::Config::Fields::Types::Text
+        class Froala < Text
           # Register field type for the type loader
           RailsAdmin::Config::Fields::Types.register(self)
 
diff --git a/lib/rails_admin/config/fields/types/hidden.rb b/lib/rails_admin/config/fields/types/hidden.rb
index 2f12148844..568ec96828 100644
--- a/lib/rails_admin/config/fields/types/hidden.rb
+++ b/lib/rails_admin/config/fields/types/hidden.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/string_like'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class Hidden < RailsAdmin::Config::Fields::Base
+        class Hidden < StringLike
           RailsAdmin::Config::Fields::Types.register(self)
 
           register_instance_option :view_helper do
@@ -22,10 +22,6 @@ class Hidden < RailsAdmin::Config::Fields::Base
           def generic_help
             false
           end
-
-          def parse_input(params)
-            params[name] = params[name].presence if params.key?(name)
-          end
         end
       end
     end
diff --git a/lib/rails_admin/config/fields/types/simple_mde.rb b/lib/rails_admin/config/fields/types/simple_mde.rb
index 3cd0b065a2..ffd72949c0 100644
--- a/lib/rails_admin/config/fields/types/simple_mde.rb
+++ b/lib/rails_admin/config/fields/types/simple_mde.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/text'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class SimpleMDE < RailsAdmin::Config::Fields::Types::Text
+        class SimpleMDE < Text
           # Register field type for the type loader
           RailsAdmin::Config::Fields::Types.register(self)
 
diff --git a/lib/rails_admin/config/fields/types/string.rb b/lib/rails_admin/config/fields/types/string.rb
index b05fadefc3..e0a322f868 100644
--- a/lib/rails_admin/config/fields/types/string.rb
+++ b/lib/rails_admin/config/fields/types/string.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/string_like'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class String < RailsAdmin::Config::Fields::Base
+        class String < StringLike
           RailsAdmin::Config::Fields::Types.register(self)
 
           def input_size
@@ -38,10 +38,6 @@ def generic_help
             text
           end
 
-          def parse_input(params)
-            params[name] = params[name].presence if params.key?(name)
-          end
-
           register_instance_option :partial do
             :form_field
           end
diff --git a/lib/rails_admin/config/fields/types/string_like.rb b/lib/rails_admin/config/fields/types/string_like.rb
new file mode 100644
index 0000000000..fcbf564844
--- /dev/null
+++ b/lib/rails_admin/config/fields/types/string_like.rb
@@ -0,0 +1,19 @@
+require 'rails_admin/config/fields/base'
+
+module RailsAdmin
+  module Config
+    module Fields
+      module Types
+        class StringLike < RailsAdmin::Config::Fields::Base
+          register_instance_option :treat_empty_as_nil? do
+            properties.try(:nullable?)
+          end
+
+          def parse_input(params)
+            params[name] = params[name].presence if params.key?(name) && treat_empty_as_nil?
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/rails_admin/config/fields/types/text.rb b/lib/rails_admin/config/fields/types/text.rb
index 5577ebae8b..3fb6ff2099 100644
--- a/lib/rails_admin/config/fields/types/text.rb
+++ b/lib/rails_admin/config/fields/types/text.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/string_like'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class Text < RailsAdmin::Config::Fields::Base
+        class Text < StringLike
           # Register field type for the type loader
           RailsAdmin::Config::Fields::Types.register(self)
 
@@ -16,10 +16,6 @@ class Text < RailsAdmin::Config::Fields::Base
             }
           end
 
-          def parse_input(params)
-            params[name] = params[name].presence if params.key?(name)
-          end
-
           register_instance_option :partial do
             :form_text
           end
diff --git a/lib/rails_admin/config/fields/types/wysihtml5.rb b/lib/rails_admin/config/fields/types/wysihtml5.rb
index 5d889b441c..f7a3b7ea88 100644
--- a/lib/rails_admin/config/fields/types/wysihtml5.rb
+++ b/lib/rails_admin/config/fields/types/wysihtml5.rb
@@ -1,10 +1,10 @@
-require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/text'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class Wysihtml5 < RailsAdmin::Config::Fields::Types::Text
+        class Wysihtml5 < Text
           # Register field type for the type loader
           RailsAdmin::Config::Fields::Types.register(self)
 
diff --git a/spec/rails_admin/config/fields/types/action_text_spec.rb b/spec/rails_admin/config/fields/types/action_text_spec.rb
index cc02ae8bc2..89f48dce66 100644
--- a/spec/rails_admin/config/fields/types/action_text_spec.rb
+++ b/spec/rails_admin/config/fields/types/action_text_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::ActionText do
   it_behaves_like 'a generic field type', :action_text_field
 
-  it_behaves_like 'a string-ish field type', :action_text_field
+  it_behaves_like 'a string-like field type', :action_text_field
 end if defined?(ActionText)
diff --git a/spec/rails_admin/config/fields/types/ck_editor_spec.rb b/spec/rails_admin/config/fields/types/ck_editor_spec.rb
index eb889ed2f9..e96b769675 100644
--- a/spec/rails_admin/config/fields/types/ck_editor_spec.rb
+++ b/spec/rails_admin/config/fields/types/ck_editor_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::CKEditor do
   it_behaves_like 'a generic field type', :text_field, :ck_editor
 
-  it_behaves_like 'a string-ish field type', :text_field, :ck_editor
+  it_behaves_like 'a string-like field type', :text_field, :ck_editor
 end
diff --git a/spec/rails_admin/config/fields/types/code_mirror_spec.rb b/spec/rails_admin/config/fields/types/code_mirror_spec.rb
index 5297c67c83..8baa35c2c1 100644
--- a/spec/rails_admin/config/fields/types/code_mirror_spec.rb
+++ b/spec/rails_admin/config/fields/types/code_mirror_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::CodeMirror do
   it_behaves_like 'a generic field type', :text_field, :code_mirror
 
-  it_behaves_like 'a string-ish field type', :text_field, :code_mirror
+  it_behaves_like 'a string-like field type', :text_field, :code_mirror
 end
diff --git a/spec/rails_admin/config/fields/types/color_spec.rb b/spec/rails_admin/config/fields/types/color_spec.rb
index afe003e482..8bd545dfbd 100644
--- a/spec/rails_admin/config/fields/types/color_spec.rb
+++ b/spec/rails_admin/config/fields/types/color_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::Color do
   it_behaves_like 'a generic field type', :string_field, :color
 
-  it_behaves_like 'a string-ish field type', :string_field, :color
+  it_behaves_like 'a string-like field type', :string_field, :color
 end
diff --git a/spec/rails_admin/config/fields/types/froala_spec.rb b/spec/rails_admin/config/fields/types/froala_spec.rb
index 2f1dd1fe68..19d207bf19 100644
--- a/spec/rails_admin/config/fields/types/froala_spec.rb
+++ b/spec/rails_admin/config/fields/types/froala_spec.rb
@@ -2,4 +2,6 @@
 
 RSpec.describe RailsAdmin::Config::Fields::Types::Froala do
   it_behaves_like 'a generic field type', :text_field, :froala
+
+  it_behaves_like 'a string-like field type', :text_field, :froala
 end
diff --git a/spec/rails_admin/config/fields/types/hidden_spec.rb b/spec/rails_admin/config/fields/types/hidden_spec.rb
index 9d3ce7d46d..ca60e2fdc0 100644
--- a/spec/rails_admin/config/fields/types/hidden_spec.rb
+++ b/spec/rails_admin/config/fields/types/hidden_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::Hidden do
   it_behaves_like 'a generic field type', :integer_field, :hidden
 
-  it_behaves_like 'a string-ish field type', :string_field, :hidden
+  it_behaves_like 'a string-like field type', :string_field, :hidden
 end
diff --git a/spec/rails_admin/config/fields/types/simple_mde_spec.rb b/spec/rails_admin/config/fields/types/simple_mde_spec.rb
index b9236234fc..6739e412b5 100644
--- a/spec/rails_admin/config/fields/types/simple_mde_spec.rb
+++ b/spec/rails_admin/config/fields/types/simple_mde_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::SimpleMDE do
   it_behaves_like 'a generic field type', :text_field, :simple_mde
 
-  it_behaves_like 'a string-ish field type', :text_field, :simple_mde
+  it_behaves_like 'a string-like field type', :text_field, :simple_mde
 end
diff --git a/spec/rails_admin/config/fields/types/string_like_spec.rb b/spec/rails_admin/config/fields/types/string_like_spec.rb
new file mode 100644
index 0000000000..c4c5fb3648
--- /dev/null
+++ b/spec/rails_admin/config/fields/types/string_like_spec.rb
@@ -0,0 +1,83 @@
+require 'spec_helper'
+
+RSpec.describe RailsAdmin::Config::Fields::Types::StringLike do
+  describe '#treat_empty_as_nil?', active_record: true do
+    context 'with a nullable field' do
+      subject do
+        RailsAdmin.config('Team').fields.detect do |f|
+          f.name == :name
+        end.with(object: Team.new)
+      end
+
+      it 'is true' do
+        expect(subject.treat_empty_as_nil?).to be true
+      end
+    end
+
+    context 'with a non-nullable field' do
+      subject do
+        RailsAdmin.config('Team').fields.detect do |f|
+          f.name == :manager
+        end.with(object: Team.new)
+      end
+
+      it 'is false' do
+        expect(subject.treat_empty_as_nil?).to be false
+      end
+    end
+  end
+
+  describe '#parse_input' do
+    subject do
+      RailsAdmin.config('FieldTest').fields.detect do |f|
+        f.name == :string_field
+      end.with(object: FieldTest.new)
+    end
+
+    context 'with treat_empty_as_nil being true' do
+      before do
+        RailsAdmin.config FieldTest do
+          field :string_field do
+            treat_empty_as_nil true
+          end
+        end
+      end
+
+      context 'when value is empty' do
+        let(:params) { {string_field: ''} }
+
+        it 'makes the value nil' do
+          subject.parse_input(params)
+          expect(params.key?(:string_field)).to be true
+          expect(params[:string_field]).to be nil
+        end
+      end
+
+      context 'when value does not exist in params' do
+        let(:params) { {} }
+
+        it 'does not touch params' do
+          subject.parse_input(params)
+          expect(params.key?(:string_field)).to be false
+        end
+      end
+    end
+
+    context 'with treat_empty_as_nil being false' do
+      before do
+        RailsAdmin.config FieldTest do
+          field :string_field do
+            treat_empty_as_nil false
+          end
+        end
+      end
+      let(:params) { {string_field: ''} }
+
+      it 'keeps the value untouched' do
+        subject.parse_input(params)
+        expect(params.key?(:string_field)).to be true
+        expect(params[:string_field]).to eq ''
+      end
+    end
+  end
+end
diff --git a/spec/rails_admin/config/fields/types/string_spec.rb b/spec/rails_admin/config/fields/types/string_spec.rb
index 50073ada07..49b95a1e9b 100644
--- a/spec/rails_admin/config/fields/types/string_spec.rb
+++ b/spec/rails_admin/config/fields/types/string_spec.rb
@@ -25,5 +25,5 @@
 
   it_behaves_like 'a generic field type', :string_field
 
-  it_behaves_like 'a string-ish field type', :text_field
+  it_behaves_like 'a string-like field type', :string_field
 end
diff --git a/spec/rails_admin/config/fields/types/text_spec.rb b/spec/rails_admin/config/fields/types/text_spec.rb
index 2351ecc728..e95cac06b6 100644
--- a/spec/rails_admin/config/fields/types/text_spec.rb
+++ b/spec/rails_admin/config/fields/types/text_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::Text do
   it_behaves_like 'a generic field type', :text_field
 
-  it_behaves_like 'a string-ish field type', :text_field
+  it_behaves_like 'a string-like field type', :text_field
 end
diff --git a/spec/rails_admin/config/fields/types/wysihtml5_spec.rb b/spec/rails_admin/config/fields/types/wysihtml5_spec.rb
index e58dba7062..0811459c00 100644
--- a/spec/rails_admin/config/fields/types/wysihtml5_spec.rb
+++ b/spec/rails_admin/config/fields/types/wysihtml5_spec.rb
@@ -3,5 +3,5 @@
 RSpec.describe RailsAdmin::Config::Fields::Types::Wysihtml5 do
   it_behaves_like 'a generic field type', :text_field, :wysihtml5
 
-  it_behaves_like 'a string-ish field type', :text_field, :wysihtml5
+  it_behaves_like 'a string-like field type', :text_field, :wysihtml5
 end
diff --git a/spec/shared_examples/shared_examples_for_field_types.rb b/spec/shared_examples/shared_examples_for_field_types.rb
index 3cd5508440..2dec54b547 100644
--- a/spec/shared_examples/shared_examples_for_field_types.rb
+++ b/spec/shared_examples/shared_examples_for_field_types.rb
@@ -23,36 +23,14 @@
   end
 end
 
-RSpec.shared_examples 'a string-ish field type' do |column_name, field_type|
-  describe '#parse_input' do
-    before do
-      RailsAdmin.config FieldTest do
-        field column_name, field_type
-      end
-    end
-    subject do
-      RailsAdmin.config('FieldTest').fields.detect do |f|
-        f.name == column_name
-      end.with(object: FieldTest.new)
-    end
-
-    context 'when value is empty' do
-      let(:params) { {column_name => ''} }
-
-      it 'makes the value nil' do
-        subject.parse_input(params)
-        expect(params.key?(column_name)).to be true
-        expect(params[column_name]).to be nil
-      end
-    end
-
-    context 'when value does not exist in params' do
-      let(:params) { {} }
+RSpec.shared_examples 'a string-like field type' do |column_name, _|
+  subject do
+    RailsAdmin.config('FieldTest').fields.detect do |f|
+      f.name == column_name
+    end.with(object: FieldTest.new)
+  end
 
-      it 'does not touch params' do
-        subject.parse_input(params)
-        expect(params.key?(column_name)).to be false
-      end
-    end
+  it 'is a StringLike field' do
+    expect(subject).to be_a(RailsAdmin::Config::Fields::Types::StringLike)
   end
 end