Getting a strong start is essential to growing healthy, productive tomato plants. Beginning indoors allows you to control early growth and get a head start on the season—especially important for gardeners in cooler climates.

Choosing the Right Tomato Seeds

Start by selecting open-pollinated or heirloom varieties suited to your climate and growing goals. Indeterminate varieties (like Large Red Heirloom or Black Krim) continue growing and producing throughout the season, while determinate types (like Homestead) produce a more concentrated harvest over a few weeks.

When to Start

Most tomatoes should be started indoors 6–8 weeks before your last expected frost date. Use a local USDA Plant Hardiness Zone to estimate.

Supplies You'll Need

• Sterile seed-starting mix (not garden soil) (or not so sterile; they'll be fine)
• Seed trays or cell packs
• Clear dome lid or plastic wrap
• Labels and waterproof marker
• Heat mat (optional, but helpful)
• Grow light or sunny windowsill
  

Planting the Seeds

1. Moisten the seed-starting mix until it's damp but not soggy.
2. Fill trays and press gently to eliminate air pockets.
3. Sow seeds about 1/8 inch deep; it is always recommended to sow seeds no deeper that the largest dimension of the seed.
4. Cover lightly with mix and mist with water.
5. Label each variety clearly.
   

Germination Tips

Tomatoes germinate best between 70–80°F (21–27°C). Place trays on a heat mat for quicker sprouting—most varieties emerge in 5–10 days.

Once germinated, remove the dome or plastic wrap and move seedlings to a bright light source. Without adequate light, seedlings will become leggy and weak.

“Tomatoes require bright light immediately upon germination to prevent stretching.”

– The Seed Saving Guide by Bevin Cohen, CC BY-NC-SA 4.0

Watering and Care

Keep soil moist but not waterlogged. Water from the bottom by placing trays in a shallow water pan for a few minutes to soak.

Once the first true leaves appear, consider transplanting into larger containers to promote stronger root development.

Successfully moving tomatoes from indoor seed trays to your outdoor garden is a critical transition. This process is called “hardening off” and helps prevent transplant shock.

What Is Hardening Off?

Hardening off is the gradual acclimation of plants to outdoor conditions—wind, sun, temperature changes, and variable moisture. Without it, even healthy seedlings can become stressed or die when planted outdoors.

When to Transplant

• Wait until nighttime temperatures consistently stay above 50°F (10°C).
• Plants should be 6–10 inches tall with at least 2 sets of true leaves.
• Soil temperature should be around 60°F (15°C) or warmer.
  

Hardening Off Steps

1. Day 1–2: Place seedlings outside in dappled shade for 2–3 hours. Bring them back inside.
2. Day 3–4: Extend exposure to 4–6 hours in partial sun.
3. Day 5–7: Allow plants to remain outside full day in full sun. Protect from wind.
4. Day 8–10: Leave overnight outdoors if temperatures are stable.
   

“Gradual exposure over 7 to 10 days gives transplants time to adjust to sunlight, wind, and fluctuating temperatures.”

– Vegetable Gardening: From Planting to Harvest by NC State Extension, CC BY 4.0

Transplanting Tips

• Plant deep. Tomatoes form roots along their stems. Remove lower leaves and bury ⅔ of the plant.
• Spacing: Leave 18–36 inches between plants depending on the variety.
• Mulch immediately to retain moisture and suppress weeds.
• Water deeply after transplanting to settle roots.
  

If frost is predicted, cover plants with floating row cover or buckets overnight to protect from cold.

Tomato plants thrive with proper watering, pruning, staking, and pest management. Regular care ensures a productive and healthy crop from summer through early fall.

Watering

Tomatoes need 1–2 inches of water per week, depending on weather. Deep watering encourages deep roots.

• Water at the base of plants to prevent fungal diseases.
• Mulch with straw or shredded leaves to retain moisture.
• Avoid inconsistent watering, which causes blossom end rot and fruit cracking.
  

Fertilizing

Tomatoes benefit from balanced nutrients. Before planting, enrich soil with compost or aged manure.

• Start with a balanced organic fertilizer (e.g., 5-5-5) at transplanting.
• Once fruit sets, switch to a low-nitrogen fertilizer (e.g., 5-10-10) to encourage fruiting over foliage.
  

“Tomatoes are heavy feeders and benefit from compost-rich soil and regular fertilization during the growing season.”

– Sustainable Gardening for the Southeast by Clemson Extension, CC BY 4.0

Pruning and Staking

• Stake or cage plants early for support.
• Prune suckers (small shoots between main stem and branches) for better airflow and larger fruit.
• Indeterminate varieties like Black Krim and German Stripey benefit most from pruning.
  

Common Problems & Organic Solutions

Problem: Blossom End Rot

Symptoms: Black sunken spot on fruit

Solution: Add calcium, maintain consistent watering

Problem: Early Bligh

Syymptoms: tBrown spots on lower leaves

Solution: Remove infected leaves, mulch, rotate crops

Problem: Aphids

Symptoms: Sticky residue on leaves

Solution: Spray with neem oil or insecticidal soap

Problem: Tomato Hornworm

Symptoms: Large green caterpillars

Solution: Hand-pick or use Bt (Bacillus thuringiensis)

Harvesting ripe tomatoes and saving seeds allows you to preserve both your harvest and your heritage. With open-pollinated and heirloom seeds, your tomatoes can become part of your family tradition.

When to Harvest

Tomatoes are best harvested when:

• Fully colored and slightly soft to the touch
• Easily detach from the vine with a gentle twist
• Still slightly underripe if expecting rain or pest issues

Leave stems attached for longer shelf life. For varieties like Breza’s Babies or Cherry Medley, harvest regularly to encourage continuous production.

Post-Harvest Storage

• Store at room temperature, not in the fridge (which dulls flavor).
• Ripe tomatoes last 2–5 days unrefrigerated.
• Overripe or cracked fruit can be preserved by canning, roasting, or drying.
  

How to Save Tomato Seeds

Heirloom tomatoes are ideal for seed saving. Choose healthy, fully ripe fruits from your best plants.

Seed Saving Steps:

1. Cut fruit in half and scoop seeds and gel into a jar.
2. Add water and ferment for 1–4 days, stirring daily.
3. Mold will form—this breaks down the seed coating.
4. Rinse seeds thoroughly in a strainer.
5. Dry on paper towels or screens in a warm, airy place for 5–7 days.
6. Store in a cool, dry place in labeled envelopes.

“Fermentation is the key to successful tomato seed saving—it removes germination-inhibiting compounds and diseases.”

– [Seed to Seed by Suzanne Ashworth, adapted in the Open Seed Source Initiative, CC BY-SA 4.0]

Label and Store

Include:

• Variety name (e.g., Chuck Yeager Tomato)
• Year harvested
• Notes on plant performance
  

Seeds can remain viable for 4–6 years if stored in a cool, dry place.

Ready to Grow Your Own Heirloom Harvest?

From seed to soil, Smoke Camp Crafts offers more than just tomato seeds—we offer a connection to creation, to heritage, and to a harvest grown with purpose. As you tend your garden, remember that every seed you plant is a testimony of care, gratitude, and the beauty of God’s design.