One of the most confusing parts of seed starting is knowing whether your seedlings are getting too much water or not enough. The symptoms can look similar, but the fix is completely different.
Here’s the beginner guide to recognizing each problem and correcting it fast.
Signs of Overwatering
Overwatering is extremely common, especially for new gardeners.
Look for these signs:
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Soil always looks wet or shiny
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Seedlings appear droopy, not dry
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Yellowing leaves that feel soft, not crispy
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Mold or algae on top of the soil
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Fungus gnats flying around the container
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Stem turning mushy near soil line
Why it happens:
Water fills the air spaces in the soil and suffocates roots, causing rot and stunted growth.
Signs of Underwatering
Underwatering is usually easier to diagnose.
Look for:
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Dry, light-colored soil pulling away from the container
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Leaves turning pale, curled, or crispy
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Seedlings standing upright but looking “thin”
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Slow or stalled growth
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Soil feels bone-dry even after stirring the top layer
Why it happens:
Seedlings have tiny root systems and dry out quickly, especially in warm rooms or strong light.
How to Fix Overwatering
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Let the soil dry out until the top half inch is no longer dark
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Increase airflow around seedlings with a fan
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Make sure your container drains well
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Avoid watering on a schedule, water only when needed
If stems have turned mushy, the seedling may not recover.
How to Fix Underwatering
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Water slowly and evenly until excess drains out
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Avoid flooding, which causes runoff and uneven moisture
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Use a spray bottle or squeeze bottle for control
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Check soil twice a day for small containers
Seedlings usually bounce back quickly once rehydrated.
The Best Watering Rule for Beginners
Press your finger into the soil about a quarter inch.
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If it feels cool and slightly moist, wait.
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If it feels dry, water gently.
This simple check prevents both extremes.