If anyone is still looking for an answer to this. I just built the system and it works on the latest FTB Unleashed. Using only AE to automate the system. This uses a subnet of AE. It is basically a stand alone AE system that manages the inventory of the Planter. Also, this will work on ANY block that has an internal inventory. If anyone has any questions after I finish writing this, I will make a video showing how to build it.
You will need:
2 colors of ME Cable (optional, you can run them so they don't interact)
1 ME Controller
3 Level Emitter
1 Storage Bus
3 Precision Export Bus
Place your MFC Planter on the ground. Place a Storage Bus on one side of it and an Export Bus on the other 3 sides of it. Place the ME Controller beside the Storage Bus. Connect the 3 Export Bus to your current AE system being careful to not let the ME Controller you just placed connect with any of the wiring that connects to the export bus. Place the Level Emitter beside each Export Bus and connect it with another color of cable to the ME Controller again, not letting it connect to the main network at all. (note: there will essentially be 2 networks, your main network which has the export bus that deposits the item into the Planter, and another completely disconnected network that is monitoring the contents of the Planter and requesting the specified items from the export bus on the first network.
Configuration:
1) set your first export bus to send only seeds, and then set it to export only with redstone signal.
2) set your second export bus to send only carrots and export only with redstone signal.
3) set your third export bus to send only potatoes and export only with redstone signal.
4) set your first level emitter by placing seeds in the item slot, setting the required quantity, and set it to emit only if below.
5) set your second level emitter by placing carrots in the item slot, setting the required quantity, and set it to emit only if below.
6) set your third level emitter by placing potatoes in the item slot, setting the required quantity, and set it to emit only if below.
7) leave the storage bus alone.
Basically, the system will use the Planter as it's main storage, then it will request items from the different export bus inputs when the specified quantities are below the threshold.
I know this is a bit long winded, and I hope it makes sense to everyone. If anyone has any questions at all, or would like me to make a video on how to set it up, i will do it.
Thanks!