|By Patty G. Leander
Americans love their tomatoes, especially when sliced on a hamburger, chopped in a salad, spread on a pizza or processed into ketchup, juice or pasta sauce. But to a vegetable gardener, the fruit of Solanum lycopersicum (formerly classified as Lycopersicum esculentum) is so much more than the end product. Whether growing to savor, share, preserve or brag, cultivating a tomato plant from the seedling stage, tending to its needs, protecting it from pestilence, observing its shapes and colors unfold, and anticipating that first warm, flavorful bite is an annual ritual. This special affinity for tomatoes is hard to explain to the uninitiated, but it’s the reason that tomatoes remain the number-one garden crop across the country. It wasn’t an easy ascent; the favored status the tomato enjoys today began a few thousand years ago.
The wild form of tomato, which wasn’t known for flavor or size, is believed to have originated in the mountainous areas of Peru, migrating through Central America and Mexico via birds and humans, taking root along the way as farmers planted, harvested and selected seeds for replanting. It wasn’t until the 1500s that Spanish explorers became acquainted with the tomato, or tomatl as it was known by the Aztecs, and brought seeds of this exotic fruit to Spain, where the Spanish, French and Italians were early adopters, incorporating tomatoes into their regional dishes. Elsewhere in Europe, the tomato was viewed with more suspicion because of its familial relationship and resemblance to toxic nightshades — pretty as ornamentals, deadly if consumed. In a roundabout journey, tomatoes returned to America with European immigrants. There the fruit began showing up in vegetable gardens and cookbooks, gradually becoming an important component of American cuisine.
Early breeding efforts focused on appearance, production and uniformity for commercial production, leading to the familiar, uninspiring red tomato found in supermarkets across the country. The heirloom movement that started in the 1980s helped shine a spotlight on flavorful tomatoes of generations past, inspiring backyard gardeners to move beyond red and round. Thankfully, today there is a tomato to please every palate, in every color of the rainbow. We can choose from thousands of heirlooms and hybrids, focusing on whatever traits are important, whether taste, early production, disease resistance, unique shape, color or compact size.
With so many varieties available to home gardeners, coming up with a manageable selection can be a daunting task. The following terms are helpful when selecting tomato varieties.
Determinate: a bush variety that is genetically predisposed to reach a determined size (ranging from 3–5 feet) and produce most of its fruit at the same time. Once fruit sets and begins to enlarge, the plant directs its energy into ripening fruit rather than vegetative growth.
Indeterminate: a vining variety that continues to grow and produce foliage, flowers and fruit until disease or freezing weather kills the plant. Indeterminate tomatoes can grow several feet tall and produce over a longer period of time. These large plants tend to have a higher ratio of leaves to fruit and all that foliage helps protect developing tomatoes from sun scald.
Hybrid: a cross of two distinct parent varieties developed by professional breeders to combine such desirable traits as disease resistance, early maturity or fruit set at high temperatures. Hybrids are produced under controlled conditions to ensure that seed maintains the desirable traits of the original cross. The resulting F1 (first generation) hybrids have vigorous, uniform growth and dependable production, year after year. Producing hybrid seed is a labor-intensive process and the extra expense involved often raises the cost. Saving seed from hybrids is not generally recommended because the resulting seed may revert to one of the lines from either parent forms and you may end up with a tomato that is different or lacks the characteristics that make the hybrid desirable in the first place. Hybrid tomatoes that possess particular traits, especially for disease resistance, are often coded by seed companies. For example, a variety with the letter F after its name indicates resistance to Fusarium wilt, a V indicates resistance to Verticillium wilt, and an N indicates nematode resistance. ‘Celebrity’ VFN is a tomato that provides resistance to all three, which makes it such a popular and dependable tomato for Texas. It should be noted that ‘Celebrity’ was introduced in 1984 by one of Texas’ own horticultural celebrities and tomato experts, Dr. Jerry Parsons, former Bexar County Extension Agent and Vegetable Specialist at Texas A&M.
Open-pollinated: a variety with fixed genetic traits that is pollinated by wind or insects. Because its genetics is stable, it grows true to type from saved seed.
Heirloom: there is no certified or official definition of what constitutes an heirloom, but there is general agreement among aficionados and experts that it must be an open-pollinated variety that has a history of being grown at least 50 years, and more specifically a variety that has been cultivated and passed down in a particular region, community or family. To many enthusiasts, the history of where or how an heirloom originated makes growing them a more fascinating endeavor, not to mention the genetic diversity and old-fashioned flavor they bring to the garden and kitchen.
Within these categories of seed type and growth habit, tomatoes can be divided further into shape and size. The varieties included within the following categories represent tomatoes that have been grown around the state. Remember that hybrids tend to produce more reliably year after year, but when it comes to growing heirlooms, trial-and-error and recommendations from other gardeners are good paths to follow.
Beefsteak: jumbo, juicy fruit that can reach 1–2 pounds in weight. However, it can take 80–90 days to grow a one pounder, which is a long time to subject plants and fruit to heat, pests and disease. Success growing beefsteaks is quite dependent on weather, and Texas is not known for accommodating gardeners with ideal tomato-growing conditions. An Instagram-worthy accomplishment if you are successful, but be sure to plant some alternative varieties in case Mother Nature is uncooperative. Examples include ‘Brandywine’ and ‘Granny Cantrell.’
Slicer: tomatoes that are predominantly round, not much bigger than a baseball, weighing in at 4–8 ounces. These globe-shaped, smaller fruits are generally more productive and less prone to cracking than beefsteaks, especially when faced with the growing conditions in Texas. Many are early to mid-season, disease-resistant hybrids, maturing in 65–75 days. Examples include ‘Celebrity’ and ‘Stupice.’
Paste: also known as plum, Italian or Roma tomatoes, these firm, flavorful tomatoes have fewer seeds and are less juicy, making them a better choice for canning, freezing, roasting, drying and sauce making. Most are determinate bush varieties, which means much of the fruit ripens at the same time, a distinct advantage when harvesting tomatoes for processing. Examples include ‘Amish Paste’ and ‘Roma.’
Cherry: a category that includes bite-size round, oval, grape and pear varieties in red, pink, yellow, green, purple, deep blue and two-tone combinations. The vigorous and productive cherry types are more able to withstand stress that comes from fluctuations in temperature and moisture, which makes them a good choice for gardens all across the Lone Star State. Round cherries tend to have thinner skin that is prone to splitting, especially if they ripen during wet weather. Grape varieties, on the other hand, have a thicker texture, described as a slight crunch, that are more resistant to splitting. Examples include ‘Matt’s Wild’ and ‘Valentine,’ a 2018 All-America Selections grape tomato bred for disease resistance and high levels of lycopene.
Currant: a different species altogether, currant tomatoes (Solanum pimpinellifolium) are more closely related to the wild form of tomato that originated in the Andes. These sprawling vines produce diminutive fruit with a burst of intense sweetness. While fun to grow and snack on in the garden, I must warn you that these are prolific reseeders. Examples include ‘Red Currant’ and ‘Sweet Pea.’
Planting and Care
Tomatoes, along with their nightshade cousins, need to go into the garden as transplants so that plants have ample time to grow, flower and set fruit before the heat of summer arrives. Growing your own transplants is a satisfying process, but if you don’t have the time or space, rest assured that commercial growers are doing the job for you and tomato transplants will start showing up at garden centers in spring. Selection is limited, of course, but most nurseries offer several varieties and ultimately any tomato you grow is going to be better than any tomato you buy at the grocery store. However, with thousands of varieties to choose from, your best bet is to peruse seed catalogs, order seeds that appeal to you and grow your own transplants. Even better, save seeds from your favorite open-pollinated varieties to plant the following year. Buying seed and saving seed put you in control of variety selection, and growing your own transplants allows you to have transplants ready at the right time for planting where you live. Not sure when to plant? Consult your local AgriLife Extension office or Master Gardener organization, ask long-time vegetable gardeners in your area or check out regional planting guides online.
Like all fruiting crops, tomatoes need plenty of sunshine for healthy growth and good production. Start with loose, well-drained soil amended with compost and fertilizer, and plant tomatoes about 3 feet apart. This spacing may seem overly generous for small transplants, but as plants grow larger, the air circulation provided by this generous spacing will help prevent disease and make plant inspection and harvesting easier. Reduce transplant shock by planting outside on a cloudy day or in the late afternoon. Moisture is extremely important when establishing plants in the garden; soak them in their containers before planting and then water with half-strength liquid fertilizer in the hole before covering up with soil. Leggy transplants can be planted sideways: remove a few of the lower leaves, dig a shallow trench, lay the plant on its side and cover the stem with soil. Tomatoes have the ability to produce roots along the buried portion of the stem.
Install tomato cages at planting time, wrapping them with fiber row cover, garbage bags or sheets to protect plants from cold and damaging winds. Also put down a 2–3” layer of mulch to help deter weeds, conserve moisture and protect soil. Try to be consistent with water in the absence of rainfall. Water needs will increase as the weather gets hotter and drier and plants grow larger.
Pests and Disease
As if the weather wasn’t enough of an issue when it comes to growing tomatoes, the plants are also a magnet for stink bugs, whiteflies, spider mites and hornworms, not to mention marauding squirrels and birds. Inspect your plants frequently and keep an eye out for signs of trouble.
Identifying a pest or disease in the early stages means it will be easier to control (less time, less pesticide, less effort) no matter what method you employ. Tomato hornworms generally show up in small numbers and are easy enough to handpick. If you must resort to sprays for other pests, turn to earth-friendly controls such as neem for stink bugs and insecticidal soap for aphids, spider mites and whiteflies. Follow label directions and note that many pests require repeat applications for control.
Alternatively, protect tomatoes with small organza bags that can be purchased at craft stores or online. Though not practical for hundreds of tomatoes, they may help prevent bird or insect damage on select prized tomatoes, especially if your bragging rights depend on it. Once a tomato plant has been ravaged by disease or pests, pull it up. It will not recover and it is not worth feeding 100 stink bugs for just one or two marginal tomatoes.
Weather, sunlight and moisture all affect a tomato’s flavor, but the most important factor in developing outstanding flavor is to let the fruit fully ripen on the vine. Easier said than done, especially here in Texas where we struggle with heat, pests and disease as tomatoes near maturity, not to mention the mockingbirds that love a sample from every tomato on every plant. A tomato picked when it just starts to blush with color, called the “breaker stage,” will eventually ripen indoors, but it will not match the full flavor that develops as sugars, acids and aroma compounds accumulate naturally in the plant. For the peak tomato experience, allow your tomatoes to stay on the vine as long as possible, even if you have to beat the mockingbirds away.
And let the bragging begin.
Flavor and Color
As Jerry Parsons declares, “taste is in the mouth of the beholder and any tomato that tastes good to you is a good tomato!”
Color affects the way we perceive tomato flavor. From the first time we look at an enticing tomato — whether a photograph, a display at a farmer’s market or a specimen we pick from our own garden — we taste with our eyes first and sometimes, but not always, our perception and the actual flavor come together for a memorable taste experience. The genetics of a tomato determines colors and influences the development of aroma and flavor compounds, but the growing conditions — sunshine, moisture, fertility — contribute to its ultimate flavor. Rating a tomato by color will have some exceptions, but the following overview may help as you determine which varieties might fulfill your expectations of a good tomato.
Red is the familiar color of supermarket tomatoes and the typical color of processing tomatoes used commercially for products like spaghetti sauce, tomato juice and ketchup. It’s what we expect from a tomato, and the flavor is a good balance of acid and sweet. Most red tomatoes have yellow skin, so the intensity of the flesh color contributes to the outer color of the fruit. Lycopene, a phytonutrient that promotes heart health and reduces cancer risk, imparts the red pigmentation to a tomato as it matures. This large color category includes ‘Celebrity’ and ‘Plum Regal.’
Pink tomatoes are the result of translucent skin over red flesh. Their flavor is often considered milder and a bit sweeter than reds, with a classic, old-fashioned taste. ‘Brandywine’ and ‘Porter,’ a true Texas heirloom developed in the 1940s by seedsman V. O. Porter, are examples of pink varieties.
Orange varieties have a sweet taste and pronounced fruitiness, sometimes described as tropical. Favorites among gardeners are ‘Jaune Flammé’ and ‘Sun Gold,’ widely considered the candy of the tomato world.
Green tomatoes, whether large or small, have a zesty or tangy flavor that is also refreshing and bright. The green color results from two genetic traits, one that prevents fruit from losing chlorophyll as it ripens and another one that limits the production of lycopene and thus the development of red pigmentation. Popular varieties in this group include ‘Green Zebra’ and ‘Green Giant.’
Black varieties tend to retain their chlorophyll while at the same time producing lycopene. The blending of the two colors (green from chlorophyll and red from lycopene), along with either yellow or translucent skin, creates varying shades of purple, maroon, reddish-brown and mahogany. Their colors are striking and the flavor is considered robust, rich and complex. Varieties in this category often win high marks in taste tests. Delicious examples include ‘Cherokee Purple,’ ‘JD’s Special C-Tex’ (developed by J. D. Brann in Conroe, Texas, more than 30 years ago) and ‘Black Cherry.’
Blue tomatoes are a relatively new introduction, the result of work by plant breeders at Oregon State University. The dark-blue pigment comes from a phytochemical called anthocyanin (the same health-promoting compound found in blueberries), which was found in wild-tomato species growing in Chile and the Galapagos Islands. These tomatoes start out green and develop a blue pigment which deepens on the areas exposed to direct sunlight. The flavor is not as wow-inducing as one might expect, but breeders are continually working on improved varieties. ‘Indigo Rose’ was the original introduction and ‘Indigo Cherry Drops’ offers an improvement in yield and flavor.
White and Yellow tomatoes are primarily low acid, with a flavor that is sweet and refreshing. Though some yellow varieties have a subtle hint of citrus, white tomatoes are considered mild and sometimes described as bland or one-dimensional. White tomatoes lose their chlorophyll without producing any other pigment. ‘Snow White’ is an ivory-colored cherry that develops a subtle sweetness as it ripens from ivory to pale yellow. ‘Yellow Pear’ is a heavy producer and ‘Azoychka,’ a large yellow slicer, is a favorite among many gardeners.
Multi-color tomatoes, from cherry to beefsteak and every shape in between, come in varying hues of stripes and splashes of color. They are as interesting on the inside as they are on the outside and their visual appeal makes them very popular with chefs and at farmers markets. Their color combinations are beautiful to bizarre and their flavors are as variable as their colors, from sweet and fruity to rich and smoky. A few examples from this diverse group include ‘Pink Berkeley Tie-Die,’ ‘Atomic Grape’ and ‘Sunrise Bumble Bee.’