[Question] Can turtles plant crops?

I attempted to use turtles to harvest and then plant crops. They seemd to harvest the crops, and seeds, just fine using turtle.dig(). However, I'm having trouble with them replanting new seeds. The problems I encountered were that if the turtle moves into the area one block above the tilled soil (groundlevel), the soil becomes untiled. So to counter that, I tried to make the turtle move two blocks above ground level and then tried turtleplaceDown() which didn't work. So then I tried having the turtle move to the side of the block, one block above ground level turn to face the block and then plant, which also didn't work.

My question: Are turtles capable of planting crops?

Currently turtles can not use/place items, only blocks. Seeds are classified as an item. Saplings however are a block and can be placed by the turtle, you can also do sugarcane and cactus if my memory serves me.

I an expert on the topic
Created farming turtles.

No they cannot plant or "plow" the land.
They can plant cacti and sugarcane!
They can "dig" the crops after grown which is my program.