I read that I can now plant a seed in pot, but I really did not understood how to do it.
I placed the pot on the ground and selected a seed but cannot plant them. What do I miss?
There must not be a previous plant in the pot, if there is one you need to remove it. You also need to click slightly above the pot to plant the seeds, not directly onto the pot.
You can't plant seeds, they're for shooting with the blowpipe. Try the alchemy plant seeds and click just above the pot.
And yes There is decay of your previous plant root which caused it to not grow. now the solution is remove the plant from the pot and do as i sadi below
Here are how to grow a seed :
Things to Note:
Four important factors needed to grow your seed out of plant is water, Pot,Temperature and Soil Every plants can be potted in any pots or containers but in the case of seeds, if its not placed in the right pots it would become either a lean or unhealthy plant which further die lack of nutrients So make sure that the Seeds should only be sowed in these types of Garden Pots
As your seed grow, continue providing the correct conditions for the plants to grow healthy and keep the medium at 70˚F or above, adding gentle bottom heat is recommended