There is no right way to start seeds for a garden. You can use almost anything that will hold soil to start your seeds with. Or even sow directly into your plants final resting place and skip starting seeds ahead of time all together. I’ve used everything from egg cartons to store bought 4 inch seedling pots to start my seeds. I am fairly new to soil blocking but it is quickly becoming my favourite way to start seeds.
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What Is Soil Blocking?
Soil blocking, like the name describes, is when you start your seeds in self standing blocks of soil rather than using seed trays or containers.
Each individual blocks acts likes it’s own container and it comes with a handy hole on the top that perfectly fits any seeds you desire.
Everything You Need To Make Soil Blocks:
- Potting mix (either home made or purchased will work)
- Fresh Water
- A soil blocker
- A container with a flat bottom to combine the potting mix with water. Large enough to fit your soil blocker. I use a 22″x15″ storage container I bought from my local hardware store.
- Trays to put your soil blocks in when made. 1020 Trays are a readily available item that are very popular for soil blocking.
- Humidity domes to cover the soil blocks to retain moisture and speed germination time.
How Do You Make Soil Blocks?
Soil blocks are made by combining potting soil with water until it’s evenly moist but not water logged. To test if you have the right amount of water simply grab a handful and squeeze it. You want to be able to squeeze a few drops of water out. In my experience it is better to have a little too much water than not enough.
When you have your soil mixture ready, grab your soil blocker and press it firmly into the soil. You’ll need to do this repeatedly until all the blocks are completely full. It helps to twist the soil blocker back and forth while pressing down to get the soil is compacted.
Once all of your blocks are full and compacted move it over to your empty tray standing by. Gently press down on the handle and give it a light wiggle to release the soil blocks.
All our soil blocks won’t be completely the same. As long as they have enough compacted soil to stand and be sturdy on their own they will do just fine.
Why is soil blocking better for my plants?
There are many advantages to soil blocking when compared to seed trays or containers.
Transplanting soil blocks is easier and less stressful for your plants.
Plants that are started in soil blocks grow strong roots due to better oxygen availability and the roots grow to the edge of the soil blocks but no further.
When you transplant the roots are waiting to reach out into new soil and establish the seedling more quickly. Since you don’t need to remove the seedling from a container their is less root disruption and less transplant shock.
Soil blocking is more cost effective.
With soil blocking, the only cost you have every year are the cost of the seeds and your potting soil. You don’t need to worry about buying new containers or seed trays. Your soil blocker will last years for approximately a $50 investment.
You can grow more plants in less space.
Soil blocking helps you maximize the space you use for starting seeds. I used 3.5 inch pots as well as soil blocking this year. In the same amount of space I started 36 seeds blocks vs 15 in the pots. That’s with me using the 2″ soil blocker. There are smaller varieties you can get to save even more space.
It is better for the environment.
Since you are not using the plastic trays or containers, there is no garbage going into the landfill. Everything you use, with the exception of the soil blocker, will be put into your garden, harvested or put into your compost.
How to water soil blocks?
Watering soil blocks can be a tricky process. The soil blocks must remain moist at all times so it is important to water on a daily basis. If the soil blocks dry out it it will be very difficult to get them re hydrated. Soil blocks need to be bottom watered to prevent deterioration of the blocks. If you top water soil blocks, they will fall apart and you will need to start over again.
The best way to water is to leave a few gaps around the edge between the soil blocks and the side of your container, as shown in the picture above. Then slowly water into those gaps until you can see that water has reached the entire bottom of the tray.
Once you’ve mastered building and watering soil blocks I am confident it will quickly become one of your favourite ways to start seeds.
I hope you enjoyed this guide. If you did make sure you check out the other growing guides, seed saving guides and our recipes. We are growing our website with more articles all the time, and we invite you to grow with us. If you have any questions about soil blocking or would like to share some of your knowledge with us please leave a comment below.