Grow sweet strawberry in a vertical PVC tube is great solution for small garden or yard. Vertical planter will save you a lot of space, at the same time keep plants out of reach from garden insect pests AND enable you to switch to hydroponics.
Elf house on a tree! That would be cute in the garden, especially in the tree over grown with ivy. How about some battery tea lights in the windows during outdoor parties. I hear the fairies/elves whispering "home school project" in my ear.
I love this idea---- Herb Garden Idea - short of space? These fragrant herbs have been planted in between pavers as a mini kitchen garden between the house and and pool. Edible ground cover is a great space-saving idea + softens hard landscaping.