Tomato (Solanum lycopersicum)

Tomato plants, also commonly called love apples and known scientifically as Solanum lycopersicum, are a staple in gardens worldwide. These rewarding plants, related to peppers, eggplants, and potatoes (all members of the nightshade family), offer a delicious and versatile fruit when properly cultivated.

At Gardencenterpoint.com, we understand the desire for a bountiful harvest of homegrown tomatoes. This guide provides everything you need, from selecting the best tomato plant varieties to buying tomato plants online and achieving optimal tomato plant growth.

Understanding Tomato Plants: Botany, Varieties, and Growth Habits

Tomato plants, while seemingly simple, have a fascinating complexity. Understanding their basic biology, the vast array of available varieties, and their specific growth needs is the first step towards a successful harvest.

Botany Basics:

• Family: Solanaceae (Nightshade Family). This explains why some people with nightshade sensitivities may also react to tomatoes.
• Life Cycle: Typically grown as annuals (completing their life cycle in one growing season), although they are technically short-lived perennials in their native tropical environments.
• Growth Stages:
  1. Seed Germination: Requires warmth (70-80°F / 21-27°C) and moisture.
  2. Seedling Stage: Development of first true leaves.
  3. Vegetative Stage: Rapid foliage growth.
  4. Flowering Stage: Production of yellow flowers, which are self-pollinating (though bees and wind can assist).
  5. Fruiting Stage: Development of green tomatoes, which then ripen to their final color (red, yellow, orange, pink, purple, or even black).
• Root System: Tomato plants develop a taproot (a main, central root) and a network of fibrous roots. A healthy root system is crucial for nutrient and water uptake.
• Important Note Proper root development is essential. A study by the University of California, Davis, found that plants with restricted root systems due to compacted soil produced 30% fewer tomatoes.

Major Tomato Plant Categories:

Tomato varieties are broadly categorized based on their growth habit and fruit type. Choosing the right type for your climate and gardening style is essential.

Category	Growth Habit	Fruit Characteristics	Best For	Examples
Determinate	Bushy, compact	Fruits ripen all at once, over a 2-3 week period.	Container gardening, small spaces, canning.	Roma, Celebrity, Rutgers
Indeterminate	Vining, sprawling	Fruits ripen continuously throughout the growing season.	Large gardens, staking or caging required.	Beefsteak, Early Girl, Sweet Million (cherry)
Semi-Determinate	Intermediate	Combines traits of both determinate and indeterminate.	Versatile, can be grown in containers or gardens.	Better Bush, Defiant PHR

Fruit Type Subcategories:

Within the growth habit categories, there are further distinctions based on fruit shape, size, and intended use:

• Slicing Tomatoes: Large, round, and juicy; ideal for sandwiches and salads (e.g., Beefsteak, Brandywine).
• Paste/Roma Tomatoes: Oblong, with dense flesh and fewer seeds; perfect for sauces and canning (e.g., Roma, San Marzano).
• Cherry/Grape Tomatoes: Small, bite-sized, and sweet; great for snacking and salads (e.g., Sweet 100, Sungold).
• Heirloom Tomatoes: Open-pollinated varieties (seeds can be saved and will produce true-to-type plants) known for unique flavors and appearances (e.g., Cherokee Purple, Black Krim).
• Hybrid Tomatoes: Crosses between two different parent plants, often bred for disease resistance, yield, or specific traits (e.g., Early Girl, Big Boy).

Choosing the Right Variety:

Consider these factors when selecting tomato plants:

• Your Climate: Choose varieties that mature within your growing season. Check your local frost dates.
• Disease Resistance: Look for varieties resistant to common tomato diseases in your area (e.g., Verticillium wilt, Fusarium wilt, late blight). Resistance codes are often listed on plant tags or seed packets (e.g., “VFN” indicates resistance to Verticillium, Fusarium, and Nematodes).
• Space Availability: Determinate varieties are better suited for smaller spaces, while indeterminate varieties require more room.
• Intended Use: Choose varieties based on how you plan to use the tomatoes (fresh eating, canning, sauce-making).
• Flavor Preferences: Explore different flavors, from sweet to acidic to savory.

How to Grow Tomato Plants: A Step-by-Step Guide

This section provides a detailed, step-by-step guide to growing tomato plants, from starting seeds indoors to harvesting ripe fruit.

Step 1: Starting Seeds Indoors (Optional but Recommended)

Starting seeds indoors gives you a head start on the growing season, especially in areas with short summers.

• Timing: Start seeds 6-8 weeks before your last expected frost date.
• Materials:
  1. Seed-starting mix (a lightweight, sterile mix designed for seedlings)
  2. Seed trays or small pots
  3. Tomato seeds
  4. Heat mat (optional, but improves germination)
  5. Grow lights (essential for strong, stocky seedlings)
• Procedure:
  1. Fill seed trays or pots with seed-starting mix.
  2. Moisten the mix thoroughly.
  3. Sow seeds ¼ inch deep.
  4. Cover seeds lightly with mix.
  5. Place trays on a heat mat (if using) and cover with a humidity dome (a clear plastic cover) to retain moisture.
  6. Once seedlings emerge, remove the humidity dome and place under grow lights for 14-16 hours per day. Keep the lights 2-3 inches above the seedlings.
  7. Water regularly, keeping the soil consistently moist but not soggy.
  8. Fertilize seedlings with a diluted liquid fertilizer (half-strength) once they have a few sets of true leaves.

Step 2: Preparing Your Garden Bed or Containers

• Sunlight: Tomato plants need at least 6-8 hours of direct sunlight per day. Choose a location that receives ample sunlight.
• Soil: Well-drained, fertile soil is essential. Amend heavy clay soil with compost and other organic matter to improve drainage and fertility. A soil pH of 6.0-6.8 is ideal. Perform a soil test to determine pH and nutrient levels.
• Container Gardening: If growing in containers, choose pots that are at least 12 inches in diameter (larger is better) and have drainage holes. Use a high-quality potting mix designed for vegetables.

Step 3: Transplanting Seedlings

• Hardening Off: Before transplanting, gradually acclimate seedlings to outdoor conditions by exposing them to increasing amounts of sunlight and wind over a period of 7-10 days. This process is called “hardening off.”
• Timing: Transplant after the danger of frost has passed and the soil has warmed up (at least 60°F / 15°C).
• Procedure:
  1. Dig holes slightly larger than the root balls of the seedlings.
  2. Space plants 18-36 inches apart, depending on the variety (determinate varieties can be spaced closer together than indeterminate varieties).
  3. Gently remove seedlings from their pots or trays.
  4. Place seedlings in the holes, burying the stem up to the first set of leaves (this encourages additional root growth).
  5. Backfill with soil and gently firm around the base of the plant.
  6. Water thoroughly.

Step 4: Watering and Fertilizing

• Watering: Water deeply and regularly, especially during dry periods. Aim for 1-2 inches of water per week. Water at the base of the plant to avoid wetting the foliage, which can promote disease.
• Fertilizing: Tomato plants are heavy feeders. Use a balanced fertilizer (e.g., 10-10-10) or a fertilizer specifically formulated for tomatoes. Apply fertilizer according to package directions, typically every 2-3 weeks. Side-dressing with compost is also beneficial. A study from the Journal of Plant Nutrition found that tomato plants fertilized with a combination of synthetic and organic fertilizers produced the highest yields.

Step 5: Staking, Caging, or Trellising

• Indeterminate Varieties: Require support to keep them off the ground and prevent sprawling. Use stakes, cages, or a trellis system.
• Determinate Varieties: May benefit from some support, especially if they are heavily laden with fruit.
• Procedure: Install supports at the time of transplanting to avoid damaging the roots later.

Step 6: Pruning (Primarily for Indeterminate Varieties)

Pruning helps improve air circulation, reduce disease, and direct energy into fruit production.

• Suckers: Remove suckers (small shoots that grow in the axils between the main stem and branches) below the first flower cluster.
• Lower Leaves: Remove leaves that are touching the ground.
• Topping: In late summer, you can “top” indeterminate plants (remove the growing tip) to encourage the remaining fruits to ripen.

Step 7: Pest and Disease Management

Tomato plants are susceptible to various pests and diseases. Regular inspection and preventative measures are key.

Common Pests:

• Aphids: Small, sap-sucking insects. Control with insecticidal soap or neem oil.
• Tomato Hornworms: Large caterpillars that can defoliate plants quickly. Handpick or use Bacillus thuringiensis (Bt), a biological insecticide.
• Whiteflies: Tiny, white, flying insects. Control with insecticidal soap or yellow sticky traps.
• Spider Mites: Tiny mites that cause stippling on leaves. Control with horticultural oil or insecticidal soap.

Common Diseases:

• Early Blight: Fungal disease that causes dark spots on leaves. Prevent with good air circulation and crop rotation. Treat with copper fungicide.
• Late Blight: Fungal disease that can rapidly destroy plants. Prevent with good air circulation and choose resistant varieties.
• Fusarium Wilt: Soilborne fungal disease that causes wilting and yellowing. Choose resistant varieties.
• Verticillium Wilt: Soilborne fungal disease that causes wilting and yellowing. Choose resistant varieties.
• Blossom-End Rot: A physiological disorder caused by calcium deficiency. Ensure consistent watering and use a calcium-rich fertilizer.

Integrated Pest Management (IPM): A holistic approach that emphasizes prevention, monitoring, and using the least toxic control methods first.

Step 8: Harvesting

• Timing: Harvest tomatoes when they are fully colored and slightly soft to the touch.
• Procedure: Gently twist or cut the fruit from the vine.
• Storage: Store ripe tomatoes at room temperature for best flavor. Do not refrigerate unless they are overripe.

Troubleshooting Common Tomato Plant Problems

Even with the best care, problems can arise. This section addresses some common issues and provides solutions.

• Yellowing Leaves: Can be caused by several factors, including overwatering, underwatering, nutrient deficiencies, or disease. Diagnose the cause by examining the pattern of yellowing and other symptoms.
• Wilting: Can be caused by underwatering, overwatering, root rot, or disease (e.g., Fusarium wilt, Verticillium wilt). Check soil moisture and look for other symptoms.
• Fruit Cracking: Often caused by inconsistent watering, especially after a period of drought followed by heavy rain.
• Poor Fruit Set: Can be caused by extreme temperatures (too hot or too cold), lack of pollination, or nutrient deficiencies.
• Leaf Curl: Can be caused by various factors, including herbicide drift, viral diseases, or physiological stress.

Advanced Tomato Plant Techniques

• Companion Planting: Planting certain herbs and flowers (e.g., basil, marigolds, nasturtiums) near tomatoes can repel pests and attract beneficial insects.
• Succession Planting: Planting new tomato plants every few weeks can extend the harvest season.
• Grafting: Joining a tomato scion (the top part of the plant) onto a disease-resistant rootstock. This technique is often used for heirloom varieties that are susceptible to soilborne diseases.
• Hydroponics: Growing tomato plants in a nutrient solution without soil.

Growing tomato plants can be a rewarding experience, providing fresh, flavorful fruit throughout the summer. By following the steps outlined in this guide, you can increase your chances of a successful harvest. Remember to choose the right varieties for your climate and gardening style, provide adequate sunlight, water, and nutrients, and be vigilant about pest and disease management.