Seeds are elements in Farm Heroes Saga. There are three types of seed in this game currently.
Grass seed
Grass seeds almost look like onions and act as a special game element. Together with a Water Drop they will create grass on that square and its four neighboring spots (horizontal and vertical). They also convert slime into grass. They are moved like cropsies. With the combination you will lose both the seed and the drop of water and also one move. On levels with few moves you may think twice before creating some grass that doesn't return much, particularly on the last moves. Levels with seeds require more luck than usual because the first moves need to match and give the necessary grass.
Hay seed
Hay seeds create hay and the playing mechanisms are the same. However, unlike with grass, hay will only be created on that single square. It will provide food for sheep and black sheep.
Flower seed
Flower seeds create flowers and the playing mechanisms are the same. Like hay seed, it will create only one flower on that square.
Grass and hay seeds
Level
Grass seeds appear first in level 161, the first level of the 12th episode, Dino District.
Hay seeds appear first in level 461, the first level of the 32nd episode, Pyramid Plaza.
Flower seeds appear first in level 586, the first level of the 39th episode, Bounty Beach.