Sweet potatoes are super easy to grow but require a long, hot growing season to become large enough to reap a good harvest. Due to sweet potatoes being an edible tuber, they help crack the ground open while also producing a ton of edible leaves that could also be used to chop and drop or make compost tea. Only the new vine tips should be harvested for leafy greens while any portion of the vine can be used to improve soil fertility. 

Sweet potato vines cover the ground to keep it moist, which is super helpful because tomato plants love water. This can help to greatly reduce the amount of water your tomato plants need to thrive by preventing the sun from baking the soil and evaporating water. 

The Camellia Sinensis Tea Bush is a great upright shrub or small tree perfect for growing a "trellis" for your tomatoes. Although tomatoes can be grown along the ground, the weight of the fruit tends to cause the entire vine to lay against the soil causing the fruit to rot or become easy prey for hungry critters. 

Because the Camellia Sinesis Tea Bush is long-lived and woody, it can be pruned into the perfect shape for keeping tomatoes well-aerated and growing towards the sun for many years to come.

To grow sugar cane is to grow a fast trellis while being able to harvest another crop, sweeter crop. Since sugar cane and tomatoes are both easy to grow, this makes an excellent introductino to the art of food gardening and companion planting. It also doesn't hurt that sugar cane will look super awesome growing in your edible garden and draw looks of awe and jealousy from all your neighbors. 

Comfrey will shade the ground and keep as much water as possible available to your tomato plants, which are very thirsty plants. So if you want to avoid having to water your tomato plants daily, this vigorous herbaceous plant will block the soil from being fried by the sun and prevent evaporation. Comfrey's strong roots will also help break up heavier soils and pave the way for equally fast-growing tomatoes to get settled in quickly for the summer growing season. 

Since asparagus must be allowed to "fern out" for the summer, it becomes a soft, upright trellis for your tomato plants. The smell of the asparagus plant may also work to mask the smell of your tomatoes to confuse tomato pests and keep your harvest safe from the would-be tomato thieves.

Asparagus plants will also provide some soft shade to your tomatoes that, despite popular belief, will produce very well with a little relief from the sun. As asparagus plants are hardy perennials, you'll have another place to grow tomatoes year after year by directly sowing your tomato seeds among the asparagus crowns. 

Grow a tomato trellis AND a second, super attractive crop. Yacon Earth Apples produce stiff, upright stems that can grow up to 6 feet tall given plenty of fertilizer. These stems will work well for smaller, cherry tomatoes for a flexible support system with lovely, fuzzy leaves. 

Of course, you can also leave the yacon earth apples in the ground to provide more humus to the soil for a perennial, soil-improving crop if you don't like yacon. In this way, you can also establish a "tomato" patch where you can grow your tomatoes each year with perennial trellises that appear each season to support your tomatoes. 

A perennial crop and a support to keep your tomatoes off the ground. Sissoo Spinach grows up to 3 feet tall and is a stiff, upright, bushy plant. Train your tomato plant up and through the "branches" of the sissoo spinach and hide them from tomato-stealing pests or let your tomatoes sprawl across the tops of the sissoo spinach if you're looking for a simple, low-labor way to keep your tomatoes growing healthily.

Growing some really large tomatoes? Then you'll need a really large, very strong support system. Why not splurge on a beautiful, immortal, "tomato cage"? Or that's what you'll call it when your friends come to cut up your card and force you to stop buying plants. 

On the bright side, a Japanese Maple Tree can become a place for your family to trellis tomatoes for multiple generations. It's like a family heirloom you keep in the ground. 

Garlic helps keep the pests away from your tomatoes (and other plants) by masking the smell of the tomato plants. If you're going organic and want to do things the most natural way possible, then planting a few pieces of garlic around your tomato plants can be the start of your garlic patch while also lending a helping hand to keeping more of your tomato harvest.