3 Reasons You Absolutely Need to Learn to Love Soil Blocking

First of all, what is soil blocking? It is a simple seed starting method. You use a soil blocking tool to press together little blocks of soil. You start your seeds in these blocks of soil rather than use a seed starting tray. Why would you need to learn to love soil blocking?
3 reasons you need to learn to love soil blocking seed starting

1. Save Space

There are many benefits of soil blocking, but the thing you'll love the most is how much space you save under your grow lights! I start 240 seedlings on a standard size cookie sheet. Under two 4' lights you can start approximately 720 seedlings! The space savings is astounding. If you are starting seeds in soil blocks rather than using seed starting trays this will also save space in storage. Since you start soil blocks on a flat tray they stack and store much nicer than all the different shapes and sizes of seed starting trays you may have collected over the years. If your indoor seed starting space is limited, you can see how soil blocking will substantially increase your seed starting capacity. 

2. Save Money

How much money you save will depend on the number of seeds you start. If you start quite a few seeds you will save quite a bit of money on grow lights, and shelving capacity, not to mention the electricity to operate all those lights. Washing and storing the flimsy plastic trays can be such a burden, and they don't last very many years before they need to be replaced. The cookie sheets or cafeteria trays should last many, many years!

3. Healthier Transplants

Roots! Soil blocks allow 'air pruning'. When the roots reach the bottom and sides of the soil block the air ‘prunes’ them, and the plant sends out new roots. Without air pruning the seedling continues to grow these original roots ‘round and ’round the plastic seed starting container. These plants become root bound, and instead of roots spreading out once transplanted they have a root clump that will be limited in its ability to obtain nutrients from the soil. 

Soil Blocking Tools:

1. You need a soil blocker which you can buy from Lee Valley in Canada, or Johnny's Seeds.
3. Scraper - could be as simple as a paint stick.
4. Cafeteria trays, or cookie sheets.  
Benefits of starting seeds in soil blocks.

Soil Blocking Recipe 

Download, print, and laminate the soil blocking recipe that I use.



1. I make my soil blocking mix in a Rubbermaid Commercial Utility Tote, you could use any low-sided container that is fairly rigid. You put a lot of pressure on the bottom of this container when you are making your blocks so you want to make sure it is a sturdy container. Press the soil blocker firmly to the bottom of your container and twist it back and forth to fill each space completely. Lift the soil blocker out at an angle to keep everything in its place. Otherwise the soil blocks can suction to the bottom of the tote and fall out before you are ready to press them out. 
2. I scrape the bottom of my soil blocker to make sure the bottom is completely level and each block is totally full.
3. Press these blocks out of your soil blocker onto a cafeteria tray, or cookie sheet. Many people use Styrofoam meat trays, I don't. I find they are flimsy and don't seem to last. 
4. Happy planting!

Don't Be Discouraged

Finally, don't be discouraged if you try and fail. Soil blocking is something that you need to learn to love. It is more finicky that filling trays with seed starting mix and planting seeds, but it is well worth the effort. It is somewhat unlikely that your first attempt will be a 100% success. There is a slight learning curve, but I am more than happy to help you get started with soil blocking. I just love the benefits!

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