Grow bags offer a simple solution for anyone who wants a container garden but doesn't have containers. Whether you've got a patio, a balcony, or simply a yard with poor soil, you can make as many grow bags as you wish for a relatively simple container garden.
Take a large, sturdy trash bag and place it in the desired location. If you think you may want to move your grow bag later, put a rug or piece of cardboard underneath it. Consider access to direct sunlight when you are deciding where to place your grow bag. For most plants, several hours of direct sun per day is desirable.
Put a layer of sand on the bottom of the bag for drainage. Then fill your grow bag with either a soilless potting mix or a mixture of equal parts sand, loamy garden soil, and peat moss.
Water the soil thoroughly and close up the bag. Then you need to decide how you want to cut your grow bag.
You could turn the bag on its side, tuck under the closed end so the bag is shaped like a pillow, and then cut several holes where you can plant seedlings or seeds. Otherwise, you could leave the bag upright, fasten it closed, and poke several holes around the sides of the bag, where you can plant seeds, cuttings, or seedlings.
Check moisture in your grow bag frequently. In warm weather, daily watering may be necessary to keep plants from getting too dry. Fertilise your plants regularly to provide the nutrients needed. If you want a growing container that will last from year to year, consider constructing a sturdy grow tube out of wide PVC pipe. Add a cover for the bottom, a chain to hang it, and then drill holes in the sides.