Customizable 2-Cell Spring Return Soil Blocker

Trade in your plastic pots in favor of soil blocks!

I love my Ladbrooke soil blocker but I needed a few more when having helpers get ready for planting. 

This design features the use of heat inserts and springs to create a durable and easy to use soil blocker. 

It would be great for garden clubs or kids who may not be able to grip larger tools. 

The included openscad files allows you to complete customize the dimensions. 

The included stl 2-cell produces 2x ~1.5" soil cubes. Comment if you'd prefer other sizes. 

Hardware: 

• 2x 50mm long x 13mm OD compression springs

• 4x 3mmx3.8mm heat inserts

• 4x 12mm length 3mm screws

Stainless variants preferred so you don't end up with rusty parts. 

If you don't want to use heat inserts, use the openscad file to reduce the hole sizes and self thread the screws into the holes.

You can resize as desired but 50mm springs are cheapest from my search. 

Print Instructions: 

Everything can be printed flat - the shaft with the dibble can printed either vertically with support on the dome or horizontally with support on the shaft to maximize sheer resistance.  Light sanding might be needed for smooth operation but the various clearances should allow it to work without issue. 

Any filament should work but PETG or any UV resistant is a great use here for when you forget it in the sun.


Usage instructions: 

Pack the cells with any seed starter material ( I prefer a 50/50 of peat/coco and compost), add water and mix until almost like a batter.

Then pack it into each cell, compressing it to squeeze the water out tightly. 

Position over your desired placement spot and pull the blocker up, leaving behind a compressed soil block with a divot to place your seed in. 

Johnny Seed's has a great walkthrough on using one.