How to Bottom Water Seed Starts in 5 Easy StepsUpdated 5 days ago

Bottom watering your seedling trays is an efficient way to grow strong, healthy seedlings. By focusing on the right tools, growing medium, and watering routine, you’ll ensure success every time.

Step 1: Start with the Right Tools

What Seeds Need to Germinate:

• Warmth and Moisture: Most seeds need temperatures between 60-70°F (15.5-21.1°C) and consistent moisture for proper germination.
• Growing Medium: Use a fine seed-starting mix with peat moss or coconut coir for excellent moisture retention. Avoid dense, clay-like mixes.

Tools Required:

• Seed-Starting Medium: Absorbent and free of large debris.
• Warm Place: Use an indoor setup, greenhouse, or a seedling heat mat for temperature control.
• Cell Trays: Choose trays like the Epic 6-Cell Trays, which allow good water entry. Ensure the bottom tray can hold water for bottom watering.

Step 2: Plant Your Seeds

Hydrate the Growing Medium:

• Hydrate Before Planting: Soak the seed-starting mix with warm water until it’s fully saturated and excess water remains.
• Fill and Plant: Fill your trays with the hydrated mix. Plant your seeds at a depth about twice their width and press down lightly.

Step 3: Keep It Moist

Top and Bottom Watering:

• Top Watering: Use a narrow-nozzled watering can or misting bottle to keep the soil surface damp, especially for surface-germinating seeds.
• Bottom Watering: Place your cell trays in a water-filled bottom tray for about 30 minutes, allowing the soil to absorb water. Drain any excess water afterward to avoid waterlogging.

Germination Domes:

• Use Domes: Place domes over your trays to maintain humidity and warmth. Keep them on until seedlings are about 1 inch tall.

Step 4: Monitor Your Trays

Testing Moisture:

• Touch Test: Feel the soil surface to check if it’s damp.
• Weight Test: Lift the tray to gauge moisture by weight—dry trays are much lighter than hydrated ones.

Rain Considerations (for outdoor growers):

• Make sure trays aren’t sitting in excess water after rain. Drain the bottom trays if necessary.

Step 5: Post-Germination Watering

Increase Watering as Seedlings Grow:

• As seedlings develop, they’ll need more frequent watering. Continue bottom watering to ensure the soil stays moist but avoid overwatering.

Monitor Growth:

• Keep a close eye on your seedlings and the moisture levels. Ensure that the soil remains consistently moist until your seedlings are ready for transplanting.

Final Checklist:

• Right Growing Medium: Use a fine, moisture-retaining mix.
• Hydrate Before Planting: Fully hydrate the medium before adding seeds.
• Keep the Surface Damp: Use germination domes and mist the surface regularly.
• Consistent Monitoring: Check moisture levels daily using the touch and weight tests. Use top and bottom watering as needed.