Ready for planting and eating.
The item id for Seed Indigo in unturned is 1105. You can use this ID with the commands below to spawn the item, give it to a player or buy it on a modded economy server.
Useable: Barricade
Build: Farm
Size_X: 1
Size_Y: 1
Size_Z: 0.2
Health: 1
Range: 4
Radius: 0.25
Offset: 0.375
Growth: 10800
Grow: 271
Explosion: 43
Blueprints: 1
Blueprint_0_Type: Utilities
Blueprint_0_Supply_0_ID: 271
Blueprint_0_Build: 27
PlacementAudioClip: Sounds/FoliagePlacement.mp3
Has_Clip_Prefab: false