I know as a single woman living alone I would feel awkward if a neighbor guy came even with a plant for no reason. My neighbor on the farm across the street brought me yummy jam to thank me for receiving a package that had been shipped to them while they were away.

If someone is new to the area (even if you), getting a plant would be a nice gesture to say....hey I am your neighbor & if you need any help with anything I can give you a hand (kinda a nice way to introduce yourself)

Sometimes it is better to just talk with a neighbor than to get gift giving into the picture since you don't know whether she might feel that even a plant gift may come with more expectations behind it.

Maybe just talk more with her & get to know her. Then around spring take a plant & say thought this would be nice for your garden.

Just coming the perspective of a single older lady.