Soil blocks might seem a bit of a garden shed mystery but they are just what the name suggests – blocks made from soil. They are used for the propagation of seeds and cuttings and are very easy to make and use. There is no need for pots or modular trays.
Soil blocks are made with a Blocker. You can make a range of sizes from micro blocks for germinating seeds to larger blocks for growing on the plants. This system requires less space and heating compared to large propagation trays.
Advantages of soil blocks and blockers
- Soil Blockers are easy to use and are made of robust zinc-plated steel construction.
- There is no need for plastic trays or pots.
- Blockers are efficient, inexpensive and maintenance free.
- Compact and easy to store.
- Small micro blocks reduce the need for large heated areas when germinating tomatoes or peppers.
- Soil blocks can be made with indentations for seed sowing, eliminating pricking out.
- Soil blocks are easy to move around and organize. If a block fails to germinate, it can simply be removed from the tray and recycled.
- With soil blocks the roots are air pruned (this means they stop growing from the tip and develop a branched root system within the block) so there is no danger of the plants becoming pot bound. It is easy to know when it is time to transplant the seedling or pot up into larger containers because you will see the roots when they reach the edge of the block.
The soil blocker system
Micro Blocker – The micro blocker is for starting small seeds. It will make 20 blocks of 20x20x20mm. When the plants are about 5cm high they should be ‘transplanted’ into the bigger blocks.
Inserts – for making indentations in the larger blocks to take the micro transplants. To use the inserts replace the rounded white plastic indentation makers ('dimples') in the top of the blocker with these cube shaped indentation makers.
Hand Blocker – ideal for the hobby gardener. Available as 4 or 5 block unit.
- Hand blocker 4: Makes 4 blocks of 50x50x50mm height 26cm,
- Hand blocker 5: Makes 5 blocks of 38x38x38mm height 26cm,
Professional Blocker – for producing large quantities of blocks
- Professional blocker 12: Makes 12 blocks of 50x50x50mm height 79cm,
- Professional blocker 20: Makes 20 blocks of 38x38x50mm height 79cm,
How to make soil blocks
- First you’ll need some blocking compost. You can either buy ready made Blocking Compost or make your own from garden compost, leaf mould and vermiculite.
- Combine your blocking mixture with water until it’s quite wet and sticky
- Load your blocker with compost. Press it down a few times to make sure all the blocks are full. When water comes out of the tops of the blocks they’re done.
- Clean off the bottom of the blocker and then press out into a tray.
Watch and learn!