Poppy Runes explained
There's one set of runes for Poppy on patch 13.24 that is the clear favorite for LoL players and pros alike. The best Poppy rune paths on the position 
Jungle are 
Sorcery as the primary path and 
Inspiration as the secondary path with a pick rate of 92%. Besides picking runes on Poppy you should learn how to play Poppy and if you are interested in pro matches take a look on how a pro builds Poppy. If you want to discuss 
Poppy then you should visit the champion subreddit.
Poppy runes from primary path
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. Other primary runes on Poppy are 
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, 
Smite. 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.
Poppy runes from secondary path
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 
Cosmic Insight and 
Hextech Flashtraption.
Cosmic Insight grants summoner spell and item haste. Having an extra way to decrease the distance with the Hextech Flashtraption will make an engage much easier to pull off.
FAQ for Poppy Runes
Which is the best keystone rune on Poppy?
The best keystone rune on Poppy is Phase Rush. This Poppy runes setup is then referred as Poppy Phase Rush.
What runes does Poppy use?
Runes from the paths Sorcery and Inspiration are the most used runes on Poppy. For the exact pick rates of Poppy runes used, you have to study the rune distribution presented.