I think a tighter crop, left and right, would make it be better. You can already see the flowers in the background and forefront. If the bike it the POI then it should take up more of the picture. And traditionally, this has weird dimensions so I don’t think it will rate as well
Good idea with the garden planter as the subject, however there are a few things that would make it a stronger photo. Firstly the highlighting in the back left competes with your subject for attention, your eye will go to the brightest area of the photo first it is automatically drawn to brighter objects, also in my opinion the crop vertically feels like it is squishing the subject in both directions I would like to see a bit more in each direction is its possible. The rear of your subject seems to be obscured by the dandelions also, maybe if you had cleared the foreground and left the ones behind you would be able to see if better. I do like the slight angle that the bike is shot on, it is just enough to give the photo a bit of depth.
I'm finding the thin and dark subject does not really stand out from the busyness of the flower bed. A different angle on it may have helped it stand out a bit more, but I'm not totally sure exactly what to suggest.