Like in Diamond & Pearl, there is an item called Honey that you'll be able to find within the game. You will first encounter this in the Floaroma Meadow after you save a man from a Galactic Grunt. He will give you 10 items of Honey to tide you over. From there, you can buy more Honey in amounts of 1s or 10s for 100 a piece. You can also obtain it with Pokémon with the Honey Gather ability
Honey Trees are the method on which you can place the Honey. After you place the Honey on a particular tree, return to it in six hours and the tree should be rustling. It has a Pokémon on it that you can now battle. This Pokémon is decided when you apply the Honey to the tree, however you will have the ability to reset in front of the tree to get the gender of Pokémon that you want. So if you want a female Combee or a Male Burmy, you'll be able to reset here until you get one. Here are the locations of the Trees throughout Sinnoh;
Pokémon Found On Honey Trees
The following Pokémon are found on all Honey Trees dotted around Sinnoh. The location does not change the type of Pokémon or the rarity.
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