herotoya wrote: 
can anybody do the maths  how many ancient spirit we can get w/o spending balens n how many balens needed to get the mount? I'm bad at maths

You will get 13 Ancient Spirit per seed if assuming no one gets to steal your crops. The seeds are 12hr btw. You get 5 seeds per quest so 65 spirits per quest = You have to do 30 quests to get the Mount unless you do the 3 Seed reward quests.
Edit : Calculated this and I call BS on whoever made up this event. This is, AGAIN, an event where gaining the mount is IMPOSSIBLE if you don't spend balens. This is how it works:
If you do all quests except Reset Mystery Shop, that costs balens, you will gain 1638 spirits if no one steals from you. If you do Mystery Shop, you'll end up with 2093 spirits. Resetting the mystery shop costs 45 balens five times a day, so it will be 225x7days = 1575 balens if you want the mount.
Note that if you have lv7 farm you can get Mount without spending any balens as each seed will yield 15 spirits if not stolen. A level 4 farm will yield 14 per seed.