Professional Seed Starting: Bootstrap Farmer Heavy-Duty Cell Inserts
Standard nursery inserts are notorious for being "single-use" plastic—cracking, buckling, and ending up in landfills after one season. Bootstrap Farmer Cell Inserts are different. Proudly Made in the USA from FDA Prime Grade, BPA-free #5 polypropylene, these inserts are built to last for years of rigorous use.
Whether you are up-potting tomatoes or starting high-volume flower crops, our inserts provide the durability and technical features required for professional-grade seedling development.
Engineered for Root Health: Air Prune Technology
Unlike standard smooth-walled pots that encourage roots to spiral and become "root-bound," our 4-cell and 6-cell inserts feature integrated Air Pruning Slits.
- The Science: When a root reaches the slit, it is exposed to air, which naturally stops its growth.
- The Result: The plant responds by sending out hundreds of tiny feeder roots, creating a massive, fibrous root system that establishes much faster once transplanted into the garden.
The 4-Cell Seed Starting Insert (Extra Deep)
Best for: Large-seeded crops and up-potting.
- Capacity: Each cell holds one cup of soil, providing ample room for vigorous growers.
- Ideal Crops: Sweet peas, peppers, tomatoes, and larger perennials.
- Fit: 8 inserts fit perfectly in a 1020 tray; 4 inserts fit in a 1010 tray.
- Dimensions: 5 ¼" x 5 ¼" x 4" tall.
The 6-Cell Seed Starting Insert (High Volume)
Best for: Flowers, herbs, and early-season vegetables.
- Efficiency: Designed for high-density growing; 12 inserts fit into a standard 1020 tray.
- Ideal Crops: Sunflowers, vine crops (cucumbers/squash), and cole crops (broccoli/kale).
- Options: Available in clear (perfect for monitoring root health) and a variety of vibrant colors.
- Dimensions: 5" x 3 ⅓" x 2 ¼" tall.
Bootstrap Farmer Cell Inserts Shop
Bootstrap Farmer 6 Cell Plug Tray Inserts | Colors
Bootstrap Farmer 4 Cell Plug Tray Inserts | Colors
Quick Comparison Guide
| Feature | 4-Cell Inserts | 6-Cell Inserts |
| Best Use | Up-potting & deep-rooted crops | Propagation & high-volume starts |
| Drainage Hole | ¾" (Extra Large) | ⅝" (Large) |
| Standard Tray Fit | 8 per 1020 Tray | 12 per 1020 Tray |
| Soil Volume | 1 Cup per cell | Approx. 0.3 Cups per cell |
| Warranty | 2-Year Guarantee | 2-Year Guarantee |
Color-Code Your Garden
Forget messy labels that wash off in the rain. Use our vibrant color options to organize your greenhouse at a glance:
- Black, Blue, Green, Purple, Pink, and Orange available.
- Use different colors for different varieties (e.g., Purple for 'Cherokee Purple' tomatoes, Green for 'Early Girl').
- Multi-Packs available for those who want a rainbow of organization.
Important Usage Notes
- Nesting: We recommend using these inserts with our Heavy-Duty 1020 or 1010 trays for the ultimate seed-starting system.
- Removal: The extra-large drainage holes at the bottom allow you to easily push seedlings out from below without damaging the stems.
- Humidity Domes: Please note that the 4-cell inserts are 4" tall and have a snug fit, making them incompatible with standard humidity domes.