Things I did wrong planting seedlings
Things I did wrong last year
I'm going to focus on my Tomato seedlings in this post. I'm planting exclusively Roma tomatoes, since that is what I'm using in my home grown meal.
1. I didn't plant enough
I didn't expect so many of my plants to die at various stages, so I planted way too few seedlings. This meant I had to regrow new batches of seedlings later in the season, eventually leading to most of my tomatoes not ripening before the first frost. This year, I'm planning for actually raising twelve tomato plants. To make sure I have enough to choose from, I've planted four times as many - 48 plants - and I've split that number between a local and a commercial variety of Roma tomato.
2. I didn't plant enough per "cell"
This was, I now know, a newbie mistake. Many seeds don't sprout, or sprout much later than others. I planted a single seed per cell in my seed starter last year, which meant many of the cells were just wasted space. This year, I planted at least four seeds per cell.
3. I planted too many varieties
I planted eight different varieties of tomatoes. I planted bushy, viny, determinate and indeterminate - big beefsteak and tiny currants. These all had completely different needs, and I had no idea how to cater to any of them.
This year I'm planting one main kind: Roma. I'm planting two varieties of it, but they are both Roma. That means I can look up information about Roma tomatoes specifically this year, and focus on learning this one thing well, rather than lots of things poorly.
4. I didn't realize I was supposed to take the plastic lid off
Once the seeds sprout, the lid is supposed to come off, it turns out. The lid helps create a warm and moist environment that encourages the seeds to sprout - this year I've taken the lid off once the seedlings have popped out, minimizing the risk of fungus and maximizing light. Speaking of which..
5. I didn't think I needed a lamp
I was wrong. Tomato seedlings want 16 hours of light per day, which they were not getting on my window sill last year. My tomato plants grew super tall and skinny in a desperate struggle to find light. This year, I have a lamp. Not a big one, not an indoor in-your-closed "tomato" grow light, but regular 800 lumen LED lamp I got at Lowes. My plants still look, I think, a bit skinny, but it's a big difference from last year.
6. Transplant to where?
Tomatoes have this amazing ability to sprout new roots if you bury their stems, and growers exploit this by transplanting the seedlings at least once before they go out to the real world. At each transplant, the plant is buried right up to the bottom set of leaves (or higher, depending on which blogs you read).
Transplanting should, although it remains a mystery to me why, be done when the seedlings have their first set of "real leaves". Real leaves being not the pair they come out of the seed with, but the first pair they grow "on their own", so to speak.
7. I didn't understand why I needed to harden off my plants (and I still don't)
This is similar to the "when to transplant" thing - everyone tells you you need to do it, but the why is frustratingly vague. "Hardening off" your seedlings means putting them outside a little bit at a time, to have them get used to their new climate. I will do this properly this year, because everyone tells me to - but I'm annoyed that I don't know what it is that happens exactly.
I think wind plays a part - being rocked back and fourth supposedly makes the plants produce stronger stems. Maybe there's also something about UV light or pathogens?