If you're looking for something that's space-efficient but can produce high yields, raised bed gardening would be the best option for you to try. Besides being efficient when it comes to space, it also solves a number of other issues, such as dealing with difficult soil as well as your garden's accessibility.

Raised bed gardens are basically made up of mounded soil that's surrounded by a frame to make sure it doesn't fall apart. They are usually at least three to four inches above the ground, and each "bed" is typically separated by a pathway. Plants would cover the entire surfaces of these beds, and the paths would provide the gardener with ample space to work in, making sure that they don't end up stepping on the soil in the process. A raised bed can be three to five feet across, and the length can vary depending on the need. You'll be able to grow a wide variety of crops of vegetables in them as well as herbs. Perennial and annual flowers also thrive in this type of gardening along with roses, shrubs, and even berry bushes.

The thing with raised beds is that they actually provide the best conditions for crop growth. Because the soil in the bed tends to be loose, deep, and fertile, it results in more efficient yields, regardless of what you plant. Of course, there are other factors to consider, but for the most part, if you do the actual planting right, you'll get good results from it.