A Radical Sprouting Experiment

I did a little experiment with sprouting cucumber seeds in soil blocks. In the left half of the tray, I put the radical (root side) down and on the right side I put the radical (root side) up.

 

 

 

For a long time now, I have noticed that old weak seed has difficulty pushing the hard seed coat off the leaves once the seedling emerges from the soil (the picture I drew demonstrates what often happens with old weak seed). 

 

 

 

 

 

This is why, contrary to what many others say, I always plant my Cucurbit seedlings with the radical at least partially up and the hard seed coat down so that the leaves can pull from the seed coat in the moist soil prior to emergence.

Swiftblocker Soil Blockers

Despite the 2020 surge in gardening interests, it seemed that there was little change in how soil blocks were being made. Since 1998, Ladbrooke was the primary manufacturer of soil blocking tools. While these tools were instrumental in helping gardeners like me produce compressed soil cubes that can be used to transplant seedlings without root shock, the difficulty in learning how to produce blocks along with the time required to do so has always been a struggle for me.

 

 

 

 

 

 

 

When watching a video of Joe Lamp’l making soil blocks in his greenhouse, I noticed that the soil blocks were being made in a different way. He had some product that enabled him to first put the soil mix in (much more dry than traditional mixes) into an outer mold, then a separate set of inner molds that press into the lower mold to compress the soil blocks. I was both captivated and interested. If someone who would normally not grow soil blocks is successful with them, perhaps there is something to this.

 

 

 

 

Many YouTube videos later, I decided I would purchase one of these blockers – if they would ever come out with a mold that made a larger 2-inch sized block. I contacted the owner of the company, Swiftblocker, to find out that they were already working on the development of such a soil blocker, the Swiftblocker 50.

 

After getting it, I tried out making a set of blocks. On the very first try, I made a beautiful set of 50 blocks in the time it would take me to make 20 blocks. Despite its larger size, because the mix does not need to be as wet, I can reuse the blocker to make more flats of soil blocks again and again until I am done with my blocking session.

 

 

 

 

 

One of the only problems that I encountered was that the Swiftblocker 50 left no room to maneuver the blocks. In order to take blocks out, I would have to move from deep trays to shallow trays. Additionally, it would be better if I had a tray that was completely flat on the bottom. The only good option for this was an Epic 1020 Universal Bottom Tray. I also bought a fully metal dough scraper to help with distributing the soil on the top of the tray before pressing it with the inner mold.

 

Lastly, I will say that I also purchased a small version of a 2.5 inch soil blocker. It didn't save as much time as the Swiftblocker 50 and, had I known some of the challenges in using it, I may have not purchased it. With that being said, if you are a small market farmer or a very big gardener, I would definitely suggest getting a larger Ladbrooke soil blocker to make your life easier.

Planting into Soil Blocks

This is not to talk about how to make soil blocks. Rather, this is just to show how I plant sprouted seeds into my soil blocks.

 

 

I generally sprout my seeds in a folded moist paper towel in a Ziploc-type bag. Once the seed has sprouted, I then plant it with the non-radical end into the side of the soil block. Leaving the radical (root side) up actually enables the seed to pull off its hard outer coat more efficiently as the stem rises up through the soil.

After inserting the seed, I cover each seed with a fine layer of sifted soil and water it in with a spray bottle. Sometimes I have to repeat the process.

Employing a consistent method for starting seed, along with a high quality soil mix ensures that transplants come up quickly and reach their potential.

Harmony Organics Soil Mixes

I cannot say enough good things about my soil supplier. The supplier that currently works for my needs is called Harmony Organics. They run Harmony Organics in the warm season and Kaz & Associates Environmental Services in the winter/rainy season in Benicia, California. The main problem that they helped me with was access to a high-quality soil mix.

 

 

 

While their mixes are no longer available in 1-yard totes, I was able to get as much as I could of the totes from them before they transitioned from cubic yards to cubic feet. Hopefully, they will be able to find a reason to once again sell in cubic yards. Until then, I will have to settle for paying more for smaller quantities of soil. Otherwise, I highly recommend these guys.

 

If you order a large enough quantity of soil and live in the area, they will deliver it to your home for a minimal price. I would simply ask for the soil to be delivered to my driveway and shovel all of the mix out of the bag. Then I would move the bag and then use a wheelbarrow and shovel to move all of the soil back into the bag. Over the years, I did multiple germination tests to make sure that the quality of the soil met my needs for both starting seedlings off in soil blocks and for putting directly into a raised bed for growing my cucumber or melon crop.

 

If I was looking for a high-quality soil supplier, I would definitely get a small quantity of soil from multiple sources, or at least different mixes to trial. Then I would do germination tests to find out what variety works best for my needs. I can say, from experience, that purchasing bad soil costs more than money – but costs much more effort and time.