You might be surprised at what can grow in a hanging container. Anything that doesn't need a lot of root space will do just fine. Berries such as strawberries are common for hanging planters. Tomatoes do well also, especially the light-weight cherry varieties, as do many types of lettuce and other greens.

To make the classic hanging basket, find a wire frame, metal mesh or even a solid plastic basket. Plastic pots can be used if you can safely fashion a way to hang them. You will also need a liner for any basket with holes in it. A liner needs to hold soil but drain water. Commonly used basket liner materials include sphagnum moss and coconut fibre, but you could also use a large piece of an old wool sweater. Alternatively, a black plastic bag with some small holes poked in it a few inches above the bottom will do the trick.

You will want to find a nutrient rich soil, preferably a fresh compost. The more concentrated the nutrients the better, as yield and quality of food will be higher. Also, since a container can dry out fast in a hot climate, adding water-retentive granules can be a good idea. These swell up upon watering and release their moisture slowly.

For multiple layers of plantings in a wire-frame or otherwise well perforated basket, fill your container part way with soil and then add seedlings of trailing fruits such as strawberries, tomatoes and small squash and cucumber varieties. Lay a few of these sideways, in alternating directions, with their roots across the surface of the soil and their above-ground parts coming out the side of the basket. More holes may need to be made in any plastic or wool liners to allow the plant to come out. Cover more soil over the roots, filling it to a few inches below the top of the basket. You can now plant another layer of trailing plants, or something that grows upright, such as lettuce, kale or basil. Even carrots could be planted here if the basket is deep enough.

Lettuce can also be planted so that it comes out of the sides of the basket, and can be planted quite densely. Harvest the largest leaves as desired, leaving the plant intact to continue growing.

Hanging gardens are also an excellent way to have fresh herbs and spices on hand. Almost any herb can be planted in one. Try oregano, rosemary, thyme or tarragon. Basil is an herb that will need to be re-planted each year, but the other varieties I mentioned should come back every spring, and even, as is the case with rosemary, provide usable leaves all year long in moderate climates.