Deep Cell Plug Tray – 2×3 Modular Seed Starter System

Start stronger seedlings with cleaner planting, healthier roots, and effortless transplanting — all in a compact, reusable deep-cell seed starting system.

This 2x3 Deep Cell Plug Tray is designed to create ideal germination and early growth conditions while eliminating the mess, soggy soil, and weak root systems common with disposable seed trays. With deep growing cells, built-in drainage, airflow, and easy ejectors, it turns seed starting into a clean, controlled, and repeatable process.

--- Growing Guide I’ve documented what I’ve learned while designing and using the Logical Grow Platform in a growing guide series on LogicalPlanet.com, covering everything from seeds through harvest. https://www.logicalplanet.com/collections/lgp/

--- Why I Designed This Every year I found myself frustrated with flimsy seed trays that warped, held water, and produced weak seedlings with tangled roots. I wanted a reusable system that actually supported healthy early growth — strong roots, proper drainage, clean handling, and compact organization under grow lights.

This plug tray was designed to fix those problems while forming the foundation of a modular growing ecosystem that can scale from seed starting into larger indoor growing setups over time.

--- Key Features - Deep 60mm growing cells for strong early root development - Root-guiding ribs in each cell to prevent circling and create dense root plugs - Drainage holes in ejectors for bottom watering and moisture control - Push-up ejector bases for clean, damage-free transplanting - Raised propagation tray creating airflow and drainage beneath cells - Translucent humidity dome with passive micro-vent spaces for controlled airflow - Compact 2x3 layout (6 cells) ideal for larger planting runs - Fully reusable and easy to clean --- Included Components - 6 deep plug cells - push-up ejector bases (print 6) - Raised propagation tray - Translucent humidity dome - Single-cell soil filling funnel for clean, mess-free filling - Reusable plant markers compatible with 12mm × 40mm labels (or handwritten notes) --- Perfect For - Starting peppers, tomatoes, herbs, flowers, and garden seedlings - Bottom watering setups - Use with seed heat mats and grow lights - Clean indoor seed starting without disposable trays - Organized multi-variety planting --- Printing & Assembly All parts print easily using common filaments and standard slicer settings. PLA works great for indoor use. For long-term durability or humid environments, PETG or ASA are excellent options. No supports required. No assembly required — all parts drop into place.

--- Related Links Logical Grow Platform (https://than.gs/m/1511734) Deep Cell Plug Tray – 3×5 Modular Seed Starter System (https://than.gs/m/1511704) Deep Cell Plug Tray – 2×5 Modular Seed Starter System (https://than.gs/m/1511705)

Join the LogicalPlanet Discord https://linktr.ee/logicalplanet

Visit my blog for more details and other designs https://www.logicalplanet.com/

--- Revisions and Updates I occasionally update and revise my designs. When I do, I’ll document the changes here. Check back periodically for the latest revision notes or if you’re experiencing any issues with a model. Please email me at [email protected] if you would like me to make a revision or have comments about this design.

2026-02-08: I have revised the bottom tray a) increasing the wall height by 4mm to make bottom watering easier, and b) moved the logicalplanet logo from the bottom to the sides to improve waterproofing (new version is 1v01).

And, I have added a watering funnel for getting water into the tray when you are ready for bottom watering.