One tool that’s growing in popularity among gardeners is the micro soil blocker. Micro soil blockers help you kickstart your garden and grow stronger, more resilient plants. This small device allows you to create compact soil blocks for planting seeds. Gardeners who add this handy tool to their seed starting toolkit will benefit in a number of ways. While starting seeds can be super rewarding, it can also be a delicate process. Getting your seedlings off to a strong start is crucial for a healthy garden!
What is a soil blocker?
A micro soil blocker is a simple, durable device that allows you to create small, compact soil blocks for planting seeds, eliminating the need for plastic pots and trays. Not only does it reduce waste, but it also promotes healthier root development, reduces transplant shock, and saves space… just to name a few benefits! A soil blocker is best used for small or medium seeds.
Recommended tool: Ladbrooke Micro Soil Block Maker
“This mini soil blocker is designed to start sowing seeds and transplant seedlings. It can make very small soil blocks and can only be used to start sowing very small seeds. It also requires the use of very fine soil blocking mix. This tool can make 20 very small blocks of 3/4inch x 3/4inch x 3/4inch.”
How it works
When you plant seeds in soil blocks, the roots can grow naturally and aren’t restricted by the walls of a pot. As the roots reach the edge of the block, they stop growing outward and start branching within the block itself. This process is called "air pruning" and it helps build a stronger root system.
When it’s time to transplant seedlings, you simply move the entire soil block into the garden or a larger container. Their root systems stay intact, which makes it easier to handle and transplant seedlings without damaging delicate roots.
This means the plant is less stressed, which helps it adjust more quickly to its new environment. Essentially, the plant skips the typical shock that happens when roots are disturbed during transplanting. Don’t forget: hardening off! Why hardening off is so important for your plants: Don’t Transplant Your Seedlings Until You’ve Read THIS!
Benefits of Using Soil Blockers
- Reduces transplant shock: Plants grown in soil blocks keep their root systems intact, making it easier to handle and transplant seedlings without damaging delicate roots. It makes for easier transplanting, too!
- Air pruning of roots: The open structure of soil blocks encourages air pruning, which helps seedlings develop strong, healthy, and non-circling root systems, leading to better plant growth.
- Less plastic waste: Soil blocking reduces the need for plastic pots or containers, making it a more environmentally friendly and cost-effective option.
- Better root development: Soil blocks encourage roots to grow outward and fill the block, improving root development and overall plant health.
- Space efficient: Micro soil blockers create small, compact blocks, allowing you to start many seeds in a small space.
- Improved water and air circulation: The loose, air-exposed soil in the blocks allows for better water drainage and airflow around the roots, preventing root rot and promoting healthier seedlings.
- Cost effective: Soil blockers last for many years, reducing the need to continuously buy seed-starting supplies like pots or trays. I’ve had my Ladbrooke soil blocker for 20 years!
How to Use a Soil Blocker
- Moisten the mix: Dampen the seed starting mix until it resembles the dampness of cooked oatmeal—moist but not soggy.
- Pack the blocker: Turn the micro soil blocker upside down. Use the back of a spoon to firmly pack the seed starting mix into the 20 square holes.
- Form the blocks: Flip the soil blocker right side up, then press it onto a tray to release the soil blocks, leaving 1/2 to 1 inch between each set of 20 cubes for watering.
- Plant the seeds: Drop a single seed (or multiple if needed) onto each soil block. For tiny seeds, you can use the tip of a damp pencil to pick them up and transfer them to the blocks.
- Mist the blocks: Lightly mist the soil blocks with water to keep them moist.
- Create a mini greenhouse: Cover the tray with plastic wrap or a lid to help retain moisture, creating a mini greenhouse effect.
- Place in a bright, warm spot: Place the tray in a warm, bright location, like a sunny windowsill or under grow lights.
- Daily check & watering: Check the blocks daily, and water as needed to keep the soil consistently moist.
- Germination: Once the seedlings sprout, remove the cover to improve air circulation.
- Water Gently: Keep the soil damp by watering gently between the blocks, irrigation style, making sure not to dislodge the seedlings.
- Transplant: When the seedlings develop their second set of leaves (the "true leaves"), they are ready to be transplanted into larger pots or directly into your garden.
Tips for Success Using Soil Blockers
- Water plants well before and after transplanting.
- When it comes time to give your seedlings their permanent home, dig a hole slightly wider than and the same depth as the container. For cabbage-family crops bury their stems up to their first set of true leaves. For lettuce, not so deep. For tomatoes, bury most of the stem, leaving just the top leaves.
- Pay attention to the weather forecast. Be ready to protect your plants with plastic milk jugs (minus their bottoms), plastic, whatever.
- Offer encouragement. Plants know what they are doing. We’re just cheerleaders. Words of encouragement like, “You can do it!” will keep your seedlings from feeling blue!
Additional Resources
Add these blog posts to your reading list to learn more about starting seeds indoors:
