I'm buying a first floor flat with a communal garden that is maintained by a gardening service. There are also individual garden plots in the front that some of the flat owners are obviously cultivating themselves. I'd like to do the same, and install a small bike shed, but I'd rather do it above board than informally.
Would you write to the freeholder to ask permission? There's nothing in the lease and there is a committee of leaseholders who arrange all the maintenance of the building and gardens. It may be relevant that the secretary of the leaseholders committee hasn't cultivated the bit in front of her flat, and she got really shirty with me when I rang her to enquire if there are informal arrangements.
I don't want to annoy my neighbour, but I'd also like to make use of the space to keep our bikes secure and grow a couple of shrubs!