One of the things that has always bothered us is how much plastic we use when growing seedlings. We usually grow in the standard 72 cell 6 pack trays. What if you could plant your seedlings without using all that plastic? Well, you can with a tool called a soil block maker. This year we decided to buy one, and just reuse our trays to hold the blocks and stop using the plastic 6 packs. Although our original intent was environmental and cost, we were surprised to find a few added benefits.
There are multiple soil block makers out there. They are basically molds you fill with very moist soil to form planting cell without the plastic to hold the sides together. It also leaves an indentation to place your seed. After you place your seeds in the indentation, you sprinkle a little soil on top and water. I’ve heard you can also use the soil right out of your garden. This is supposed to result in less of a shock to the plant on transplant since the medium is the same. Not purchasing seed starting soil can also save you money if you are on a small budget.
We were planting tomatoes at the time of transitioning between our last 6 pack insert and the first tray of soil blocks. The last tomato tray was planted 3 days before we started planting in the soil blocks so those plants had a 3 day head start. The first benefit we found was we could fit more plants in the trays, and the seedlings have more soil than the 6 packs allowed. The second benefit was the soil blocks germinated faster and at higher rate. Every soil block germinated. They are also growing faster than the ones in the inserts regardless of the 3 day head start! I took a picture of the side by side comparison.
The only downsides to this new method we’ve been able to see so far is you have to get the consistency of the soil just right or the block will break apart. You also have to water very carefully so you don’t erode the soil. A lesser issue…I like to plant multiple varieties in a single tray while I’m testing which varieties sell best. Without plastic walls there is no way to keep a plant marker standing upright in the tray. Not a big problem but it annoys me.
All in all I’m excited to see the end results on transplanting. I’ll give you an update then!
See a demonstration of the soil block maker starting our first tray on the 5280 Artisan Farm YouTube Channel: