diff --git a/CHANGES.txt b/CHANGES.txt
index af0d40db38..fa57f6b4d7 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -43,6 +43,8 @@ Features
 Bugfixes
 --------
 
+* Use ``http`` as fallback in plugin/theme installers if a SSL error occurs
+  (Issue getnikola/nikola-themes#49)
 * Add missing ``xmlns:xhtml`` namespace to sitemaps (Issue #1890)
 * Fixed superfluous rebuild problems with Python 3. Note that this will cause
   rebuilds for most sites. (Issue #1887)
diff --git a/nikola/plugins/command/install_theme.py b/nikola/plugins/command/install_theme.py
index 4937509710..a243b2ceb9 100644
--- a/nikola/plugins/command/install_theme.py
+++ b/nikola/plugins/command/install_theme.py
@@ -27,7 +27,7 @@
 from __future__ import print_function
 import os
 import io
-import json
+import time
 import requests
 
 import pygments
@@ -95,8 +95,13 @@ def _execute(self, options, args):
         if name is None and not listing:
             LOGGER.error("This command needs either a theme name or the -l option.")
             return False
-        data = requests.get(url).text
-        data = json.loads(data)
+        try:
+            data = requests.get(url).json()
+        except requests.exceptions.SSLError:
+            LOGGER.warning("SSL error, using http instead of https (press ^C to abort)")
+            time.sleep(1)
+            url = url.replace('http', 'https', 1)
+            data = requests.get(url).json()
         if listing:
             print("Themes:")
             print("-------")
@@ -124,9 +129,18 @@ def _execute(self, options, args):
     def do_install(self, name, data):
         if name in data:
             utils.makedirs(self.output_dir)
-            LOGGER.info("Downloading '{0}'".format(data[name]))
+            url = data[name]
+            LOGGER.info("Downloading '{0}'".format(url))
+            try:
+                zip_data = requests.get(url).content
+            except requests.exceptions.SSLError:
+                LOGGER.warning("SSL error, using http instead of https (press ^C to abort)")
+                time.sleep(1)
+                url = url.replace('http', 'https', 1)
+                zip_data = requests.get(url).content
+
             zip_file = io.BytesIO()
-            zip_file.write(requests.get(data[name]).content)
+            zip_file.write(zip_data)
             LOGGER.info("Extracting '{0}' into themes/".format(name))
             utils.extract_all(zip_file)
             dest_path = os.path.join(self.output_dir, name)
diff --git a/nikola/plugins/command/plugin.py b/nikola/plugins/command/plugin.py
index 391a7c9953..ea8b073654 100644
--- a/nikola/plugins/command/plugin.py
+++ b/nikola/plugins/command/plugin.py
@@ -30,6 +30,7 @@
 import shutil
 import subprocess
 import sys
+import time
 import requests
 
 import pygments
@@ -209,9 +210,18 @@ def do_install(self, url, name, show_install_notes=True):
         data = self.get_json(url)
         if name in data:
             utils.makedirs(self.output_dir)
-            LOGGER.info('Downloading: ' + data[name])
+            url = data[name]
+            LOGGER.info("Downloading '{0}'".format(url))
+            try:
+                zip_data = requests.get(url).content
+            except requests.exceptions.SSLError:
+                LOGGER.warning("SSL error, using http instead of https (press ^C to abort)")
+                time.sleep(1)
+                url = url.replace('http', 'https', 1)
+                zip_data = requests.get(url).content
+
             zip_file = io.BytesIO()
-            zip_file.write(requests.get(data[name]).content)
+            zip_file.write(zip_data)
             LOGGER.info('Extracting: {0} into {1}/'.format(name, self.output_dir))
             utils.extract_all(zip_file, self.output_dir)
             dest_path = os.path.join(self.output_dir, name)
@@ -296,5 +306,11 @@ def do_uninstall(self, name):
 
     def get_json(self, url):
         if self.json is None:
-            self.json = requests.get(url).json()
+            try:
+                self.json = requests.get(url).json()
+            except requests.exceptions.SSLError:
+                LOGGER.warning("SSL error, using http instead of https (press ^C to abort)")
+                time.sleep(1)
+                url = url.replace('http', 'https', 1)
+                self.json = requests.get(url).json()
         return self.json