diff --git a/actioncable/Rakefile b/actioncable/Rakefile
index d61d38d8e7..87fa4d2933 100644
--- a/actioncable/Rakefile
+++ b/actioncable/Rakefile
@@ -10,6 +10,8 @@ task default: :test
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 Rake::TestTask.new do |t|
   t.libs << "test"
   t.test_files = FileList["#{__dir__}/test/**/*_test.rb"]
diff --git a/actionmailbox/Rakefile b/actionmailbox/Rakefile
index 92d1bba635..353f526344 100644
--- a/actionmailbox/Rakefile
+++ b/actionmailbox/Rakefile
@@ -6,6 +6,8 @@ require "rake/testtask"
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 Rake::TestTask.new do |t|
   t.libs << "test"
   t.pattern = "test/**/*_test.rb"
diff --git a/actionmailer/Rakefile b/actionmailer/Rakefile
index 6ac408e1cb..d0d6733343 100644
--- a/actionmailer/Rakefile
+++ b/actionmailer/Rakefile
@@ -7,6 +7,8 @@ task default: [ :test ]
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 # Run the unit tests
 Rake::TestTask.new { |t|
   t.libs << "test"
diff --git a/actionpack/Rakefile b/actionpack/Rakefile
index cddc536d3b..02e1c6d96d 100644
--- a/actionpack/Rakefile
+++ b/actionpack/Rakefile
@@ -9,6 +9,8 @@ task default: :test
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 # Run the unit tests
 Rake::TestTask.new do |t|
   t.libs << "test"
diff --git a/actiontext/Rakefile b/actiontext/Rakefile
index 4d6d7f4265..112f347b9d 100644
--- a/actiontext/Rakefile
+++ b/actiontext/Rakefile
@@ -6,6 +6,8 @@ require "rake/testtask"
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 Rake::TestTask.new do |t|
   t.libs << "test"
   t.test_files = FileList["test/**/*_test.rb"].exclude("test/system/**/*", "test/dummy/**/*")
diff --git a/actionview/Rakefile b/actionview/Rakefile
index 6aa58d5fa6..03f45bdaab 100644
--- a/actionview/Rakefile
+++ b/actionview/Rakefile
@@ -10,6 +10,8 @@ task default: :test
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 # Run the unit tests
 
 desc "Run all unit tests"
diff --git a/activejob/Rakefile b/activejob/Rakefile
index 0529c24a7d..4971d15774 100644
--- a/activejob/Rakefile
+++ b/activejob/Rakefile
@@ -10,6 +10,8 @@ task test: "test:default"
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 namespace :test do
   desc "Run all adapter tests"
   task :default do
diff --git a/activemodel/Rakefile b/activemodel/Rakefile
index c9a9d197c1..13002ebada 100644
--- a/activemodel/Rakefile
+++ b/activemodel/Rakefile
@@ -6,6 +6,8 @@ task default: :test
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 Rake::TestTask.new do |t|
   t.libs << "test"
   t.test_files = FileList["#{__dir__}/test/cases/**/*_test.rb"]
diff --git a/activerecord/Rakefile b/activerecord/Rakefile
index 414d62f219..6c4c7ad595 100644
--- a/activerecord/Rakefile
+++ b/activerecord/Rakefile
@@ -23,6 +23,8 @@ task default: :test
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 desc "Run mysql2, trilogy, sqlite, and postgresql tests"
 task :test do
   tasks = defined?(JRUBY_VERSION) ?
diff --git a/activestorage/Rakefile b/activestorage/Rakefile
index 0d71f44595..be476acd30 100644
--- a/activestorage/Rakefile
+++ b/activestorage/Rakefile
@@ -4,6 +4,8 @@ require "bundler/setup"
 require "bundler/gem_tasks"
 require "rake/testtask"
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 Rake::TestTask.new do |t|
   t.libs << "app/controllers"
   t.libs << "test"
diff --git a/activesupport/Rakefile b/activesupport/Rakefile
index fd60a14155..4c48dfc887 100644
--- a/activesupport/Rakefile
+++ b/activesupport/Rakefile
@@ -6,6 +6,8 @@ task default: :test
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 Rake::TestTask.new do |t|
   t.pattern = "test/**/*_test.rb"
   t.warning = true
diff --git a/railties/Rakefile b/railties/Rakefile
index 19a0e7b9e3..74f6c9be7d 100644
--- a/railties/Rakefile
+++ b/railties/Rakefile
@@ -7,6 +7,8 @@ task default: :test
 
 task :package
 
+ENV["RAILS_MINITEST_PLUGIN"] = "true"
+
 desc "Run all unit tests"
 task test: "test:isolated"
 
diff --git a/railties/lib/minitest/rails_plugin.rb b/railties/lib/minitest/rails_plugin.rb
index e57643f6d8..a61ef3087d 100644
--- a/railties/lib/minitest/rails_plugin.rb
+++ b/railties/lib/minitest/rails_plugin.rb
@@ -110,7 +110,7 @@ def self.plugin_rails_options(opts, options)
   # minitest-reporters, maxitest, and others.
   def self.plugin_rails_init(options)
     # Don't mess with Minitest unless RAILS_ENV is set
-    return unless ENV["RAILS_ENV"]
+    return unless ENV["RAILS_ENV"] || ENV["RAILS_MINITEST_PLUGIN"]
 
     unless options[:full_backtrace]
       # Plugin can run without Rails loaded, check before filtering.