What is Soil Blocking?

What are soil blocks?

Soil blocks are made using a handheld tool called a soil blocker, which is pushed into your wet soil mix, packed tightly, then the blocks are pushed out and placed on a waterproof tray with at least a half inch rim.  You can then plant seeds right away into your soil blocks!

Why make your own soil blocks?

Using soil blocks when starting seeds can bring a myriad of benefits to gardening.  It is an excellent approach to seed starting that allows gardeners to eliminate waste, cost over time, and storage issues that arise when seed starting.  There is no need for plastic seed starting trays or inserts due to the soil blocks ability to hold its form.  Soil blocks also encourage air pruning, which can lead to denser root development before planting.

Not only is it cost-effective, but you can make a custom mix of living soil rather than use a sterilized blend.  The seedlings can benefit from beneficial microbes and large healthy root systems due to the cube shape.  When you transplant your seedlings into the ground, there is no disturbance to the roots or plant from pushing them out of a pot.

How to care for soil blocks and seedlings:

Keep your blocks covered until the seeds germinate.  Once they are going strong remove the cover, give them plenty of light, and keep them evenly moist but not soggy.  You can add water to the bottom of the tray to allow the blocks to soak up the moisture or mist them regularly.

Steps for making ready-to-use soil blocks:

1. Using your blocker, dip into your moist soil mix (wet like a sponge) and fill all the block spaces up.

2. Lift up the blocker and scoop up and fill any gaps in blocker with soil and press it in lightly with your fingertips.

3.  Use something with a blunt flat edge like a garden knife or spatula to scrape off any excess soil from the bottom of the blocker.

4.  Place your blocker onto a tray and press down firmly.  You can see some extra water welling up around where the blocker is tightly compressing your blocks.

5.  Release the blocks onto the tray, and continue making more until you have what you need.

6.  The blocks are now ready for seeds!

Organic Soil Blocking Recipe:

Soil blocking mix is easy to make! This is just one recipe you could use. You can also use a commercial soil mix. It is best to wet your mix some hours before you make blocks to improve penetration of water into the planting medium.

• 1 700g brick coconut coir fiber (2.5 gallons when hydrated)

• 1 gallon HealTerra Soil Enrich

• 12 quarts Seacoast Compost

• 4 quarts perlite

• 1 lb box of Down To Earth Starter Mix 3-3-3

Optional Items:

1 quart worm castings

1 cup greensand