Growing Tomatoes – An Engineer Looks at Support Design

Bill Devlin
Adams County Master Gardener

In a past life, I confess to being a Coast Guard Engineer. Very few engineering designs succeed on the first try. For example, Thomas Edison went through 18 months of trials on his light bulb filament material before he had any success. Those of us growing tomatoes go through our own periods of trial and error before we hit on the appropriate support design that produces the best tomatoes. In staking tomatoes, many gardeners begin with a single stake supporting a single tomato plant pounded into the ground just deep enough to keep the stake and the young tomato plant standing vertically. In mid summer after the plant has grown much larger, produced a lush crop of tomatoes and been subjected to a 3-inch July downpour, we find the plant toppled over on the softened ground, exposing the tomatoes to rot and ruin. From an engineering viewpoint, this predicament inspires a look at other alternatives.

Can a single stake do the job? Yes, if it’s very firmly anchored. How firmly? For a single stake, probably a foot into the ground will do it. How to get a foot deep? Two suggestions are offered. Use either a breaker bar which is a heavy steel bar with a sharpened business end or a narrow drain spade, 6 inches wide and 16 inches long. Either will make a pilot hole that can get the recommended 12-inch depth for a single stake support system. Be aware, though, that a tomato supported by a single stake requires more maintenance, with the gardener having to tie up the various branches of the tomato plant to the stake every week or so to keep the plant growing securely.

At the opposite end of the tomato-support spectrum is a frame design my late uncle constructed. He was employed as a salesman for a metal utility building company that gave him access to their machine shop. As he had an 18-acre fishing lake, he traded access to that for favors. The shop guys constructed to his specifications, an 18" x 18" 4-sided frame with 12" ladders on the sides to keep the tomatoes in. They were 5 feet long and of half-inch rebar welded at the corners. Driven into the ground with a sledge hammer, they would withstand soaking rains, and I suspect but cannot prove they would probably have withstood a Category 2 Tornado. Fortunately we never had the opportunity to put that possibility to the test.

Between these two extremes, I have decided upon 4-legged structures made of decay resistant wood on which to grow my tomatoes. My choice of wood is the old Kansas standby, Osage orange. This is a very durable wood used for 40 year life expectance fence posts and extremely hot burning firewood. If you fill a wood stove completely with ‘hedge’, as we affectionately call it, you are in serious danger of melting the stove, but I digress.

By going to a 4-legged structure, you have the benefit of stability without the need to go very deep as you must for a single stake. This is especially useful if you don’t have a ‘breaker bar’ or a ‘drain spade’. I have built a two-plant version with the exterior dimensions of 18" by 24", with two plants 22" apart in the longitudinal dimension. I have also braced the upper rung of the ladder structure with 45 degree angle braces and angled the rungs to get the strength of a truss. The Osage orange, as the name implies, is a bright orange color when freshly cut that fades to a modest gray as it weathers. I use galvanized Phillips head screws with the holes pilot-bored to eliminate splitting. This is very important with Osage orange. The lower ends of the 5 foot long narrow boards are sharpened, and I drive them into the ground 6 inches for stability. The more ladder rungs used, the less maintenance (poking the tomato branches back in) is needed. Again, some rungs should be mounted at angles for the rigidity that a truss provides. An example of this kind of tomato support is shown in the accompanying picture.

Another support method that can be used incorporates 4 separate supports. In this version, ‘T’ steel fence posts are driven into the ground past the anchor plate for stability. Tomato branch support is provided by sisal twine. These support structures are particularly effective when constructed against white buildings as the heat reflected off the buildings raises the temperature and hastens ripening and yield of the tomato plants.

Don’t forget to collect used egg shells which can be crushed and used to mulch the tomato plants. The crushed shells will reduce or eliminate ‘blossom end rot’ caused by a calcium deficiency in our high rainfall soils, especially this year. If you have further questions about this tomato cage or for higher definition photos, please email me at

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