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Yesterday night/morning an animal buried this acorn in my 5th floor balcony flower pot
(sh.itjust.works)
Photo of flower pot with red houseleek and some grass coming out between the remnants of the Edelweiss that died a few months ago and a fresh hole with a single acorn in it.
I sure hope your balcony can hold the weight of an oak tree.
In that pot it can only become a bonsai, but I will probably rip it out before it comes to that and the animal doesn't retrieve it's food until next year, because the roots could come out through the pots bottom drain holes and cause damage.