Incubate – Seedling to Plant
In Part 1 we discussed growing viable seedlings that can be incubated into a healthy plant. I have found that just transplanting the seedling into a larger pot does not provide the best possible growing conditions for the seedling. I think they still need a little TLC, so I use my seed starter to get the seedling to a growth stage that allows for continued growth success.
First Transplant
It is now time to transplant your seedlings into a larger pot. I transplant my plants a couple of times to continue to promote root growth. My first transplant is into a 2-inch square pot. The second transplant is into a 5-inch pot and for my tomatoes I do a third transplant into a 9-inch deep pot.
My trick for an easy way to transplant from the starter tray to a 2-inch pot is to use ice cube tongs. The process is as follows. First get a small metal ice tongs. If the ends are angled straighten them out so that the tongs slide easily along the edge of the seedling cell. Take a small 2-inch pot and add starter mix to the top, push down about 3/4 of an inch or so to compact and then top off with more starter mix. Strike off the top off the mix to be level with the top of the small pot. Then take two fingers and make an indentation in the soil that is two fingers wide and as deep as the seed cell. Firm up the side of this opening by wiggling your fingers.
Take a small paring knife and scrape the edges of the seed cell where your seedling is. This frees up the mix in contact with the cell wall to make the extraction of the seedling with the tongs easier. Take the tongs and slide along the edges of the cell wall all the way to the bottom. Do not press down to hard or the cell bottom will crack. Squeeze the tongs and while continuing to squeeze, lift out the seedling and place in the hole you made in the pot, pressing down gently into the hole. Release the squeeze pressure on the tongs and lift it out. Firm the starter mix around the transplanted seedling.
As you can see from the photos, these are tomato seedlings and they only have the two leaves that come from the emerging seed pods. Using the ice tongs method allows for minimal if any disturbance of the seedling so that you can make this transplant earlier, just after the seedling takes shape. This helps avoid a leggy seedling and gets them into a small growing pot earlier.
Seedling to Second Transplant
I want my seedlings to grow into an established plant that can be transplanted into an increasing larger pot. (Depending on the type of plant, I may transplant from a 2-inch pot to a 5-inch pot to a 9-inch pot before a final transplant into the garden). At this stage, the seedling is still fragile and requires a little extra care while growing. I place my seedlings, that are now in 2-inch pots, into a controlled environment, that I created from a clear plastic storage bin. (See my Seed Starter post for more on the Seed Starter). I drill a hole in the lid of the storage bin so that I can add a lamp and place the bin on a heated mat to maintain a constant soil temperature for the seedlings in the pots.
See above photos of my Seed Starter. I have a small one with a single lamp and the larger bin shown above that has 2 grow lamps. A simple plug in timer on the lamp allows it to be on for about 16 hours a day. I also use a soil heating mat that keeps the soil temps at a constant 77 degrees. I place a Accurite weather sensor in the bin to monitor the bin temps. If the temperature climbs to high when the lights are on, I raise the lid to create an air gap for ventilation. It may take a few trials over a few days to get the temperatures adjusted properly.
This makes for a perfect environment for taking a plant from the seedling stage to about 2 inches in height with multiple healthy leaves (about 2-3 weeks). At that point you can be very comfortable transplanting into a 5-inch pot. Set them under a grow light, in a south facing window sill or in your greenhouse. Soon, you will have a 6-inch-high or greater plant that can be hardened off and planted in the garden.
