Poppy Runes explained
There's one set of runes for Poppy on patch
11.20
that is the clear favorite for LoL players and pros alike. The best Poppy Runes on the position 
Jungle are Sorcery as the primary path and
Inspiration as the secondary path with a pick rate of 29%. Besides runes you should take a look on Poppy Build and if you are interested in pro matches take a look at Poppy Probuilds. If you want to discuss
Poppy then you should visit the champion subreddit.
Primary path on Poppy
Sorcery empoweres abilities of Poppy and increases the available champion resources. Most of high elo players – and our LoL pros in the the major regions – have agreed that
Phase Rush is the best keystone rune to run on
Poppy.
Phase Rush offers more flexibility and options to betake oneself in and out of danger, which can be helpful since that's essentially the main playstyle of Poppy. This is usually followed up by taking
Nimbus Cloak,
Celerity and
Waterwalking.
Nimbus Cloak, which grants movement speed upon using a summoner spell, works amazingly well with junglers in particular as they take the shortest cooldown summoner spell,
Celerity boosts all movement speed bonuses to Poppy.
Waterwalking grants movement speed in the river, which helps Poppy get around the map quicker. The extra damage will also help in those all important dragon and baron fights.
Secondary path on Poppy
When it comes to your secondary path, most
Poppy players prefer to go with
Inspiration.
Inspiration opens creative opportunities on Poppy troughout the match. On the
Inspiration path, the best runes for Poppy are
Hextech Flashtraption and
Cosmic Insight.
Having an extra way to decrease the distance with the
Hextech Flashtraption will make an engage much easier to pull off.
Cosmic Insight grants summoner spell and item haste.
FAQ for Poppy Runes
Which is the best keystone rune on Poppy?
The best keystone rune on Poppy is
Phase Rush.