Going up: Want more lettuce or strawberries? Try this mobile planter. Since it’s easy to wheel around, you can plant earlier in spring and move seedlings into the garage on cold nights, extending the growing season.
Another version on rain gutter gardening. Want to grow a salad garden but have no room? Try gutters! Affix them to a fence, slope them for drainage, and voila! Of course,for this I'd need a backyard wider than a hallway.