Fresh-from-the-garden, sun-warmed, sweet, juicy tomatoes are probably the Number One reason why people start gardening. Be forewarned! No store-bought cousin will ever measure up once you have experienced the Real Deal!
Native to South and Central America, tomatoes have been cultivated for over 3,000 years. Prior to 31 October 1548, Italy had no tomato sauce. It’s hard to imagine, isn’t it? Now, as winter fades, many gardeners feel compelled to plant tomatoes. While starting too soon is a waste of time and seeds, tomatoes can be started indoors 6 to 8 weeks before the last frost date.
Commonly grown as annuals, tomatoes (Solanum lycopersicum) are actually perennial plants, in their native regions. These members of the nightshade family, along with eggplants and potatoes, are self-pollinating. This means that honey bees and other pollinators can carry pollen from one flower to another, on the same plant, to cause a plant to create fruit. Of course, the more plants you have, the higher your pollination rates will be. Plus, you can never have too many tomatoes, right?
Shopping for tomato plants
Spring garden shows and plant sales draw gardeners like moths to flame. This is especially true about tomatoes. With so many varieties, colors, and sizes to choose from, we tend to get carried away. To be fair, who doesn’t want to try growing that new black, striped, pear-shaped variety with a nice citrusy aftertaste? So we fill boxes, bags, and the backseat with countless new and old favorite tomato plants and head home. Very often, those store bought tomato plants are root bound. If you buy tomato seedlings, be sure to handle the plants gently as you transition them from greenhouse city life to life in your yard. Also, as dreams of heirlooms and hybrids dance through your head, remember that tomatoes, like all other plants, can be vectors for pests or disease. When you bring new plants home, be sure to place them in a quarantine area until you are sure they are healthy.
What is your tomato type?
Tomato plants are classified as either determinate or indeterminate. Determinate plants, also called ‘bush’ tomatoes look like 3 to 5 foot shrubs and all the tomatoes ripen within a 4 to 6 week period. This is perfect if you plan on canning your bounty. It doesn’t really work if you are growing tomatoes for fresh eating. Indeterminate tomatoes put out a continuous crop all summer and fall, providing a similar sized crop, but spread out over time. You can also use the UC Davis chart on tomato varieties, if you are growing in California.
How to grow tomatoes
Tomatoes are easily grown from seed or cuttings. They grow best in the ground, but can also be grown in containers or straw bales. Seeds should be planted 1/4” deep. Keep the soil moist, but not soggy. As seedlings emerge, they can be hardened off and moved outdoors, as long as they are protected from chilly nights and strong winds. Germination of most tomato seeds usually takes 5 to 10 days in warm weather. Colder temperatures slow the process. Give your tomato seedlings a boost with fish emulsion. Keep weeds away from your seedlings, so that they can get a healthy start. As your tomato plants get bigger, you may want to provide some support with tomato cages or stakes.
Pinching your tomato plants
No, I don’t want you to be mean to them - well, maybe a little. Pinching back excess growth can make more nutrients available to whatever is left, plus it stimulates flower and fruit production. On the other hand, if you take away too many leaves, your tomatoes can get sunburned. Yellow or green shoulders on otherwise red fruit is also a sign of too much sun exposure. Pruning tomatoes is a balancing act between sun protection, fruit production, and disease prevention. Deficit irrigation can also be used to significantly improve the flavor and increase the sweetness of your homegrown tomatoes.
Prune your tomato plants so that they have two or more stems starting near the base of the plant. If you pinch your plants to make a central stem, it will produce fruit earlier, but at lower quantities. Use this image to help you pinch back your tomatoes properly:
Tomato pests & diseases
Hornworms and blossom end rot are the two most common problems faced by California tomato growers. Blossom end rot is caused by an erratic calcium supply, which occurs whenever watering is irregular. A regular watering schedule can reduce blossom end rot in tomatoes, as well as leaf roll, cracked fruit, catfacing, and citrus fruit split. Tomato hornworms are large and can devour an amazing amount of foliage before you even know it. Achemon sphinx moths look a lot like tomato hornworms, but they are mostly limited to grape vines.
Other common tomato pests include tomato fruitworms, tomato pinworms, Eriophyid mites, bagrada bugs, blister mites, green fruit beetles, Japanese beetles, nematodes, leaf-footed bugs, leaf miners, oriental fruit flies, stinkbugs, spider mites, whiteflies, treehoppers, weevils, cutworms, and voles. And squirrels. Always squirrels.
Tomato diseases include tomato ring spot, tomato spotted wilt, alternaria stem canker, fusarium wilt, tobacco mosaic virus (TMV), grey leaf spot, anthracnose, verticillium wilt, stem blight, and powdery mildew. Many of these diseases can be prevented with regular crop rotation.
Tomatoes grown from seed will develop a taproot. What’s really strange is that tomatoes grown from cuttings will not.
If we ever meet in person, be sure to ask me about Wally's s****y tomatoes!
I hope this information inspires you to grow more of your own food. You can ask your garden questions on my Home page.