It gets expensive purchasing vegetable transplants from your local store. Especially when you are farming on a larger scale. In addition, there really isn’t a great assortment of vegetables when purchased in that form.
We grow Organic, mostly Heirloom vegetable varieties that you can only purchase by seed. Organic for the health value and Heirloom for the amazing flavor! So we grow our plants from seed indoors.
At first we bought plastic trays and plastic pots and found it to be too much plastic for our environmental view. It was also bulky and took a lot space. We had 4 shelves full of trays with heat pads, and lights overhead on each shelf.
We quickly found just reusing a few trays with small soil blocks and no plastic pots was a way to save money, time, electricity and it uses less seedling starting mix. It also results in less plastic in the landfill. We saved the pots we already purchased in case we have a streak of bad weather and have no choice but to repot the soil blocks into the bigger pots.
You can buy soil block makers in a variety of sizes. We bought the smallest one. The larger ones allow the smaller blocks to fit inside the new, larger block the next size up. So you could theoretically start with the smallest blocks then transplant them twice into larger blocks until you have quart size plant.
We only grow our starts for 3 weeks which seems to be exactly when the roots of the seedling fills the small block. We plant outside at that time. If the weather is bad, we transplant the seedlings to small pots, which we had to do this year with our basil.
Best of all we are able to plant almost twice as many seedlings in a tray. We get close to 80 plants out of one tray now.
See how we make our soil blocks on the farm’s YouTube Channel:
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: