If you have ever grown tomatoes, you know they have to be trellised. If this is going to be your first year growing tomatoes, understand that “they have to be trellised”. I have yet to meet the tomato bush that does not grow so big that it can fully support itself. I guess that’s not true really. All tomatoes can support themselves in their own way. However, their way involves sprawling all over the ground. This sprawl will work fine for the tomato since all it really cares about is reproducing. It doesn’t care if its seeds are in fruit lying on the ground or if the seeds are in fruit that is 6’ up in the air. However, as gardeners, we care very much where the tomato seeds (fruit) are on the plant. Because of this, if you are going to grow them successfully, you have to support them.
Why Trellis? – Since the tomato plant has the ability to create roots anywhere along its stem, tomatoes vines will root wherever they touch the ground. This will create an ever wider and wider bush if left alone. All of that vining uses up nutrients that can and should be channeled into fruit production. Trellises allow you to prevent this. A properly trellised tomato will have one and only one point of contact with the soil. This will allow you to control branching and keep your fruit from lying on the ground where it will quickly cause rot and attract insects, bunnies and other pests.
Trellising adds support to limbs that can become very heavy when laden with fruit. High winds are the enemy of large tomato plants and the trellis will provide extra protection against it. Also, trellising allows you the added support needed to open the bush up through pruning. This increased air flow through the plant allows moist plants to dry quickly (thus limiting fungal infections). An open bush also makes tomato harvest easier and it provides access to the inside of the bush if you need to apply organic or inorganic pesticides.
Types of Trellises – Trellises can be very simple or very elaborate. You have to decide what works best for you. A local greenhouse grows a hydroponic “tomato forest”. Their vines grow ten to twelve feet in the air. They grow these massive vines by clipping them to a single nylon cord attached to the roof and the growing area. You can’t get much simpler than one string!
Probably the most commonly used trellises are those welded wire rings that we get at the big box or local garden center. While convenient, I have found that even the largest ones sold are inadequate for my needs. If you are growing two or three plants in pots, the store bought “cages” will probably be fine for you. If you are going to buy cages, I recommend you buy the biggest ones available. Since these cages are made out of small gauge wire, their welds are weak and they will begin to break apart after just a few uses.
A common homemade version of the tomato cage is made by bending a heavy gauge wire mesh into a circular cage. These work very well, but storage can be a problem. Since they can’t be stacked inside each other (like the store bought cages) they can take up a lot of room in the garage. Also, since they don’t have long wire “legs” like the store bought version, you will have to find a way to stake them. Rebar and zip ties work very well for securing them to the ground.
My friend Bill Adams cuts cattle panels into three sections and then ties them together in a trianglular shape with metal clips (read more about these in his book “The Texas Tomato Lover’s Handbook”). These are really great. They are tall enough and strong enough to support the bushiest tomatoes out there. After assembly, he uses a “T-Post” to secure the cage in place. Theses “cattle panel cages” are durable enough to last a lifetime. Plus, they provide a perfect surface to add shade cloth. Shade cloth can do so much for your tomatoes. If you use it when you first put the plants out, you can easily add a top to the shade covered cage to keep in heat and avoid damage from a late season cold snap. The shade cloth will also protect your tender young plants from sun scald, wind damage and also add some insect protection. While there is some cost associated with this method, your cages will give you a lifetime of service. In addition to durability, they are also very practicle. At the end of the season, you can easily disassemble them and store your panels flat against the garage wall.
I also use cattle panels to support my tomatoes. However, I don’t cut my panels up. I line my tomato rows with cattle panels on each side of the row. I place my panels about 32’ to 36” apart and support them with T-Posts. As the tomatoes begin to bush, I can slip bamboo lengthwise through the panels to support any branches that become heavy with fruit. There is one slight drawback to my method. Since the tomatoes are grown between panels, I have to do all of my harvest and pruning “through the fence”. However, the squares on the panels are large so this is only a minor inconvenience.
In my potager, I grow my tomatoes on “decorative” trellises that I made by wiring together small cedar limbs. These trellises are very attractive and, since they are cedar, they last a very long time. While not as functional as the cattle panels or the cages, they work well for determinate tomatoes. This year, I am growing romas in them. Roma tomatoes create a nice, neat, and compact bush that do not require as much support as an heirloom or big indeterminate like “Better Boy”.