Whatsaat Wednesday 11

I don't think anyone contributed to Whatsaat10 last week, but Shutterup (whose brainchild this challenge was) was away from home then. Anyway I thought I'd do a "Whatsaat 11" blip today for a bit of fun. I decided it looked best in mono.

Clue (if you need it) I use it in spring & autumn.

Go on, have a guess - or maybe you know for certain?