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Troubleshooting Tomato & Pepper Seedling Collapse

Seedlings that sprout then suddenly die after removing a humidity dome likely succumbed to drying out or temperature swing.

Key Conditions

Germination temp: 70–80°F constant.
Post-germination: 60–70°F to prevent legginess.
Soil: evenly moist, never bone-dry.
Light: 40W fluorescents 2–3 inches above plants, 14 hrs/day.

Recovery?

If seedlings are shriveled and brown, they’re dead—start over. If green but fallen, a quick drink may revive them, but repeated stress yields poor plants. Best to restart with strict moisture and temperature control.

Peppers germinate slower (up to 21 days) than tomatoes (5–7 days).

Seeding and Propagation: Starting Daylily Seeds in Cold Climates (Zone 3-4); Starting Hot Peppers from Seed: The Heat Secret; Growing Thick-Stemmed Tomato & Pepper Seedlings: Light, Temperature & Variety Secrets; Saving Sweet Pea Seeds: Harvest, Drying, and Storage; Starting Lavender from Seed: Timing, Light, and Soil; Tomato Seeds Do Not Need Freezing: Simple Germination; Planting Kumquat Seeds: No Soak Needed, but Expect Variability; Saving Melrose Pepper Seeds for Next Season; Venus Flytrap Seed Germination: Pure Peat Moss Method; Saving and Starting Jalapeño Seeds at Home

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