Many plants are best grown on a support structure, to keep the plants upright and to allow you to keep the growth habit under control. Additionally, some plants (especially large fruiting plants like tomatoes) will tend to fall over without some sort of support, which can lead to crimping of the stems and diminished plant health.
Plants can be grouped into 3 categories, according to height:
- Small plants (< 1 foot tall). These do not need any external support. Includes lettuce, cabbage, and oregano.
- Medium plants (1-3 feet tall). These may benefit from some supporting. Includes basil, dill, and peppers.
- Large plants (> 3 feet tall). These definitely need some support. Includes tomatoes, cucumbers, melons and squash.
Growing outdoors in the ground provides plenty of good options for supporting your plants, including stakes, cages, trellises, fences, and so on. These options usually rely upon pushing the bottom of your support structure into the dirt for maximum stability. However, if you are growing inside, or even outside on a concrete patio, you will have to explore some alternative ways to support your plants.
To support large plants growing outside, the easiest way is to simply prop up a wooden trellis near your bucket. Train new growth towards the trellis, and tie the growing plant to the trellis using flexible garden tape.
Another great support structure for large outdoor plants is a giant PVC cage. I make mine about 9 feet tall, which requires a stepladder to reach the top. Using 1/2-inch PVC, this type of cage is inexpensive to build, and if you connect all the pieces without glue (dry-fitting), then the structure can easily be disassembled for storage or transport. As the plant grows taller, use stretchable garden tape to loosely secure the plant to the PVC. Be sure to place some heavy items (such as bricks) at the bottom of the structure to weigh it down and keep it stable in the wind. I learned this the hard way: I once grew a large tomato plant held up by my tall PVC cage, and I let the fluid level in the bucket get too low, which made the whole thing quite top-heavy. Along came a wind storm, which knocked everything onto its side. What a mess!
In the case of medium-sized plants, supports are often a good idea. For instance, when I grow basil plants in a 5-gallon bucket, they stand up fine until they get about 12-inches tall, and then they sometimes fall over. This happens because the plants’ net-pots are not fixed to the bucket lid, so the plants are free to rotate and fall. To keep the plants upright, I recommend either a miniature version of the PVC cage described above, or a wire tomato cage, attached around or inside the bucket. I have found that a 42-inch metal tomato cage fits snugly around my 5-gallon buckets, and provides great support for my basil plants. Alternatively, the grower in this video (starting at 2:09) has drilled holes in their bucket lid and then inserted a tomato cage directly inside the bucket.
One last method to consider is the “scrog net”, used by many marijuana growers. This is a horizontal netting system, through which the plants grow. If you have a large enough growing space, this could be a good option. You could even create a multi-tiered net system to support the plants at different levels.