Tomatoes (How to Plant, Grow & Care for) – GIY Plants

Sweet juicy tomatoes (Solanum lycopersicum) are the prize of any garden. Nothing motivates people to take up gardening more than the desire to eat a tomato right off the vine.

Supermarket tomatoes look perfect but often taste unripe and have little flavor.

Planting your own tomatoes is a great way to grow more exciting and tastier varieties, such as heirloom tomatoes.

Most people are familiar with red globe tomatoes, but tomatoes come in a variety of types, complex flavors, and colors (e.g., red, pink, purple, brown, yellow, orange, white, green, and even striped).

Technically considered fruits, tomatoes belong to the nightshade family of plants (Solanaceae), which includes familiar relatives such as potatoes, eggplant, bell peppers, petunia, and even tobacco plants.

Tomato Plant Care

Tomatoes can be fussy and difficult-to-grow plants for beginners.

Tomatoes require careful upkeep (staking, mulching, pruning, etc.) and lots of sunshine, nutrients, and water to remain happy.

Late-maturing tomatoes can take more than 85 days to mature, making them harder to grow in colder climates. However, early harvest types like cherry tomatoes are great for shorter summers.

Despite their challenges, tomatoes are satisfying, nutritious, and worthwhile.

Below, we’ll go over everything you need to know to grow the juiciest, sweetest, and healthy tomatoes, even if you’re a beginner.

Soil

Tomatoes grow best in well-draining, slightly acidic (pH 6.2-6.8), fertile loam soil high in organic matter.

Tomatoes will also grow in sandy soils or any soil other than heavy clay.

Watering

Tomatoes need about 1-1.5 inches (2.5-4 cm) of water a week, ideally divided between two heavy soakings.

Water from the bottom at the soil level with a soaker hose or drip irrigation to prevent diseases and pests.

Water daily during the first week of planting, and increase weekly watering to 2 inches (5 cm) when flowers bloom.

Avoid soggy soils, as this can cause root damage.

Lighting

Tomatoes require full direct sunlight, with a daily minimum of 4-6 hours, or ideally 8 hours.

In hot climates where temperatures exceed 85°C, some partial shading will help prevent heat stress-related issues.

If grown indoors, place tomatoes near a south or southeastern-facing window for the most sunlight.

Humidity & Temperature

Relative humidities between 50-70% are ideal, with humidities greater than 60% shown to enhance self-pollination significantly. [1]

The optimum growing temperature for tomatoes is 70-75°F (21-24°C) during the daytime and 60-65°F (16-18°C) at night.

If temperatures consistently rise above 85°F (29°C), consider partial shading or growing tomatoes closer together (to create shade) or in containers indoors.

Fertilizing

Tomatoes are hungry plants, so fertilize during planting and again every 3-4 weeks with about 1 pound (0.5 kg) of fertilizer per 100 sq. ft. (9 sq. m.) of garden space.

Use a fertilizer with about half as much nitrogen as phosphates and potassium (NPK ratio: 5-10-5 or 5-10-10) because high nitrogen may cause excessive vine growth and twisted foliage, which delays flowering and reduces yields.

For the most accurate results, do a soil test before applying fertilizer.

Diseases & Pests

Tomatoes are prone to many diseases and problems, including tomato leaf curl, blossom end rot, blossom drop, cracking, weed spray damage, and other nutritional deficiencies and foliage diseases (e.g., early blight, septoria leaf spot, fusarium wilt, verticillium wilt, powdery mildew, yellow leaf curl disease, etc.) [2].

Fruitworms, cutworms, and hornworms often infect tomatoes. Other common pests include aphids, flea beetles, leaf miners, spider mites, stalk borer, and stink bugs.

Treat fungal diseases and insects with fungicides or insecticidal soap. Horticultural oils such as neem or peppermint oil also work well in warding pests.

Avoid getting leaves wet by watering at the bottom (soil level). Mulching can also prevent water splashback, which brings diseases from the soil onto leaves. Crop rotation, weeding, and pruning also help prevent infections.

Days to Maturity or Harvest

Tomatoes have a wide range of growing seasons, depending on the type:

• “Early” types take 45-60 days from transplant to maturity. Cherry tomatoes, like Patio Choice, mature earlier and take only 45-50 days.

• “Midseason” types take 60-75 days and are great for cooler climates, where fall temperatures can dip.

• “Late” types take 75 days or more, such as Beefsteak tomatoes, which average 85 days.

For directly seeded plants, add another 25 days.

How to Grow Tomatoes for Beginners

Tomatoes can be grown from seeds indoors or from starter plants. Plan to start seeding 6-8 weeks before the last frost. To grow tomatoes:

From seed.

Sow seeds about ¼ inch (0.5) cm deep in flats containing sterile soilless germination mix or potting soil. We recommend peat moss with a bit of perlite, bark ash, and some starter fertilizer. Do not use regular garden soil, as it’s often not airy enough and may contain fungi.

Keep temperatures warm, from 75-85°F (24-29°C), with a heating mat or on top of a refrigerator until seedlings emerge. Keep soils moist. If using a cloche, give the seedlings airflow once in a while.

Use a bright overhead light. Without lights, seedlings will fall over.

Thin seedlings after true leaves appear, allowing two inches (5 cm) between most viable seedlings.

Once plants reach 5 inches tall (6-8 weeks), reduce watering, and place plants outdoors in the shade and protected from wind for a few hours at a time to harden them off. Gradually expose to sunlight over the next two weeks as well before transplanting. [2]

From seedlings/starters.

Purchase seedlings from nurseries, saving you a month of gardening time. Make sure starters are bright green, have hardy stems, and are free of pests and diseases.

If not transplanting immediately into the garden, re-pot any plants which appear root bound or have become too leggy.

Seedlings grown inside greenhouses or indoors should also be hardened off over two weeks.

Transplant seedlings after the last frost and when soil temperatures are at least 60°F (15°C). Water before transplanting and daily after that for one week before weaning down to 1-1.5 inches (2.5-4 cm) of water a week. Apply some fertilizer when transplanting to support growth.

How to grow tomatoes from a tomato.

Growing a tomato plant from a tomato fruit is as easy as removing the seeds, planting directly into potting soil or soil mix, and covering it with some dirt.

Some say planting slices (3-4 per container) leads to faster growth, but the results are mixed.

Water after planting, and keep soil conditions moist and warm by covering the container with a plastic bag or cloche. Seedlings should start to germinate from seeds in 2-3 weeks.

Types of Tomato Plants

Tomatoes are often divided into a few common categories:

• Determinate vs. indeterminate types or bushing vs. vining types. Indeterminates grow indefinitely, while determinates tend to be more compact.

• Heirloom vs. hybrid or open-pollinated vs. F1 types. Heirlooms grow true to type and have a provenance. Some say heirlooms also taste better. Here are our recommendations for the top 10 best-tasting heirlooms.

Beyond these broad categories, tomatoes are also categorized as follows:

• Cherry tomatoes are a hybrid of wild currant-type and domesticated tomatoes. These small circular early-to-harvest tomatoes come in red, orange, yellow, and black. Cherry tomatoes are tartier and sweeter than regular tomatoes and are great for snacking or salads.

• Grape tomatoes look like grapes and tend to be smaller than cherry tomatoes. They tend to have meatier flesh and thicker skin, making them taste less sweet and tart than cherry tomatoes.

• Roma tomatoes, also known as Italian tomatoes, are larger than cherry and grape tomatoes but not as large as regular slicing tomatoes. They look like oblong plums with pointy ends. They have few seeds and are great for canning, sauces, or pastes. They also tend to have chewier flesh and less water content.

• Beefsteak tomatoes are the largest tomatoes in regular commercial production. They are known for their large, ridged, irregularly shaped fruit, weighing up to a record-breaking 7 lbs. 12 oz (or 3.51 kg). These are considered the classic slicing tomatoes. There are both heirloom and hybrid Beefsteak types.

• Globe tomatoes are the most common supermarket variety. They have thin, snappy skins and juicy interiors. For the best-tasting Globe tomatoes, avoid picking light red, pink, or super firm ones, which tend to lack flavor and juiciness.

• Cocktail tomatoes, also known as “tomato-on-the-vine,” are in size between cherry and globe tomatoes. They’re sometimes called Campari tomatoes. This hybrid is known for its juiciness, high sugar, low acidity, and lack of mealiness.

• Green tomatoes are often associated with American Southern cuisine. They’re usually breaded and fried, used in salsa, or pickled. Green tomatoes are just unripened end-of-harvest tomatoes. Some heirloom tomatoes, however, do grow green when ripened, but the common term green tomatoes refer to the unripened variety.

10 Most Common Problems Growing Tomatoes

Tomatoes are notorious for their demanding and sensitive natures.

Below is a list of the ten most common problems encountered when growing tomatoes:

1. Yellowing leaves can occur for many reasons but are usually a sign of nutritional deficiencies, diseases, or pests.

2. Leaves curling are usually signs of heat, wind, and drought. However, they can also happen because of moisture stress, excess nitrogen, over-pruning, pests, viruses, or exposure to herbicides.

3. Tomatoes not turning red or ripening are most commonly associated with hot temperatures but can also indicate nutritional imbalances (N, P, K, Mg), overwatering, white flies, overcrowding, or viruses.

4. Blossoms dropping are signs of heat, light, humidity, pests, fertilization, or soil issues.

5. Fruits rotting, also known as blossom-end rot, is associated with environmental stresses causing cells to die. It’s often closely associated with calcium deficiencies.

6. Overcrowding can happen if tomatoes are not spaced far apart enough. Overcrowding leads to competition for nutrients, less growth, and lower yields.

7. Over- or under-pruning affects yields and blossoming. Over-pruning can also cause sunburn and leaf curl. Underpinning leads to excess foliage and vines that may reduce pruning. When pruning, focus on pruning only suckers between the primary and lateral stems rather than pruning the growing tips, which stresses the plants.

8. Mealy tomatoes usually happen on the vine when tomatoes are stressed, converting sugars to gritty starch. Causes include high temperature, overwatering, underwatering, and improper nitrogen and nutritional balance in the soil.

9. Pests and diseases frequently affect tomatoes, causing damage to crops, leaves, and the entire plant. Tomatoes are especially prone to fungi, viruses, and leaf-eating pests. To reduce pests, practice companion planting, which consists of growing beneficial secondary crops such as basil next to tomatoes to keep pests away.

10. Misshapen fruit (e.g., bumpy shoulders and catfacing) often happens because of low temperatures, usually below 60°F (16°C). Cracking fruit is another common problem and is a sign of excessive moisture after a dry period, high temperatures, inadequate nutrition, or sudden temperature changes.

Tomato Plant Support Options

Most indeterminate tomatoes will grow indefinitely, so it’s best to secure them to some support structure as they grow to keep fruits off the ground, save space, and prevent them from damage and diseases.

Below are some common ways to support tomatoes as they grow:

• Trellis or staking is the most common method of securing tomatoes. For indeterminate tomatoes, make sure your stake or trellis is at least 6 (1.8 m) tall and 3 feet (1 m) for determinates. As the main vines grow, secure them to the stake or trellis with twine or string to stand them upright.

• Caging works best for determinate tomatoes, but larger cages can also work with indeterminate types. Plant your tomatoes, then place the caging over them. Secure vines to the cylindrical cages as they grow.

• Overhead Suspension. Create a clothesline and suspend ropes down from the line. The hanging ropes act essentially the same as stakes. As vines grow, secure them to the suspended rope. This method is easier and cheaper than staking but can be challenging for crop rotation.

• Teepees. Place 3-4 poles together, spaced at the bottom but jointed at the top like a teepee. Secure tomato vines to the poles as they grow. This method provides a more secure structure (won’t fall over) and keeps tomatoes inside the teepee from getting sunscald.

• Florida Weave. This method, also known as the cat’s cradle method, involves using sisal strings to create suspension lines that support tomatoes as they grow every ten inches off the ground. Place two strong poles at the end of the garden bed, then create suspension lines every 10 inches (25 cm) off the ground. Weave the strings back and forth so that the tomatoes are supported between the strings at every level.

• Japanese Ring. This method involves planting 3-4 tomato seedlings outside the edge of a 3-feet diameter wire ring cage filled with nutrient-rich organic matter in a center feeder pile. This method is supposed to help tomatoes grow stronger roots with better nutrient uptake in the center. Tomato plants growing around the ring will also shield each other with shade.

Growing Tomatoes in Pots

You can also grow tomatoes in containers, with grow bags, or in raised garden beds, which may help with soil quality, spacing, and drainage issues.

We recommend containers that are at least 18-20 in. (45-50 cm) in diameter and 24 in. (60 cm) deep with a volume of at least 20 gallons (~75 liters) if you’re growing tomatoes on the larger end.

Tomato Benefits

Tomatoes are low in calories and high in fiber, vitamins, and nutrients. They are also a good source of antioxidants such as lycopene and beta-carotene.

100g of ripe, raw, year-round average red tomatoes contain:

• 94.5 g of water
• 18 calories
• 0.88 g of protein
• 0.2 g of fat
• 3.89 g of carbs
• 1.2 g of fiber
• 2.63 g of sugars
• Varying amounts of calcium, iron, magnesium, phosphorus, potassium, sodium, zinc, copper, manganese, selenium, fluoride, and vitamins A-C, and K.

Below, we summarize some key tomato nutrients and their purported benefits [3]:

Key Nutrients	Purported Benefits
water	Hydration and body temperature regulation
fiber	Aids in digestion, good for gut health, and beneficial for teeth and gums
calcium, iron, magnesium, phosphorus, potassium, sodium, zinc, copper, manganese, selenium	Helpful for regulating blood pressure and hydration levels; promotes heart health, among other mineral benefits
vitamin A	Benefits vision and immune systems
vitamin B	Helps Improve metabolism, creates new blood cells, and maintains healthy skin, brain, and body cells
vitamin C	Protects the body from cellular damage; strengthens the immune system and may help lower blood pressure; involved in collagen production and iron absorption
vitamin K	Needed for blood clotting and wound healing. Good for bone health
lycopene	Antioxidant and anti-inflammatory that may help prevent prostate, breast, and lung cancer, as well as heart disease
beta carotene	Helps with immunity, skin, cardiovascular, and eye health.
naringenin	Found in tomato skin, this flavonoid helps decrease inflammation, prevent stomach damage, and reduce heart disease risks. Also has antimicrobial and anticancer properties.
chlorogenic acid	An antioxidant that may help lower blood pressure.
chromium	A mineral that helps regulate blood sugar, reducing risk of diabetes

Frequently Asked Questions

References:

[1] Shamshiri, R. R., Jones, J. W., Thorp, K. R., Ahmad, D., Man, H. C., & Taheri, S. (2018). Review of optimum temperature, humidity, and vapour pressure deficit for microclimate evaluation and control in greenhouse cultivation of tomato: a review. International Agrophysics, 32(2), 287–302. https://doi.org/10.1515/intag-2017-0005.

[2] Tong, C., Schuh, M., & MacKenzie, J. (2022). Growing tomatoes in home gardens. University of Minnesota Extension. https://extension.umn.edu/vegetables/growing-tomatoes.

[3] Kris Swartzendruber, (2022, January 21). Tomatoes provide many health benefits. Michigan State University Extension. https://www.canr.msu.edu/news/tomatoes_provide_many_health _benefits.