I always put off thinning. It's delicate work, removing tiny stems from around another tiny stem, and I worry that the seedlings that are left after the process, shell-shocked by their new-found space, will flop over and die on me. So I wait to thin, justifying my procrastination with logical-sounding thoughts. Some of the seedlings may die anyway, so I'd better wait before I remove any of them, I might tell myself, or, If I wait, the strongest seedlings will emerge and then I will know which ones to remove. Instead, entire rows of seedlings grow taller, fighting for access to the light, and thicker, intertwining with each other as they produce their second set of leaves.
Over-seeding gets me into this problem in the first place. I could avoid over-seeding by using one of those seed-planting devices that can be dialed to space tiny seeds, like lettuce and arugula, a half inch or inch apart, so that ten seedlings don't germinate in one spot. With medium-sized seeds, like beets and chard, I could carefully place seeds in the ground an inch or so apart. Yet I usually don't bother to space seeds unless I'm planting beans or peas or corn, which have seeds so large that they even have directionality, as in, plant this side down.
I don't over-seed strictly out of laziness, though, admittedly, I do save a bit of time and frustration by not worrying where exactly I set that last, mini-dirt-clod-looking beet seed. I over-seed because germination is not guaranteed. Sometimes, as with my row of arugula, every seed appears to germinate, creating a crowded, unbroken row of green, but sometimes, as with my row of chard, germination is so-so, creating a row of already-spaced seedlings that might have been over-spaced had I placed seeds every inch. And, sometimes, as with my row of lettuce, germination is delayed, which means that many seeds will be lost to rot in the meantime. Two weeks after planting, stimulated by cooler soil temperatures, the lettuce seeds are finally germinating.
This morning I thinned rows of cool-season-greens seedlings. The bok choy and Chinese kale were the easiest to thin because their seedlings had the thickest stems, which stood tall as I clipped their neighbors at the soil. The beet seedlings bled magenta as I cut them, and their leaves stuck to each other, making it almost impossible to remove seedlings without disrupting their neighbors. The remaining beet seedlings flopped over from the stress. The chard seedlings were equally floppy but not nearly as crowded, allowing me appreciate their mix of yellow, pink, and red stems as I thinned a few places along their row. The lettuce row, where only a few plants had germinated last week, surprised me with recent germination and a few tiny lettuces to thin.
The arugula row was the most crowded with seedlings and therefore the most challenging to thin. The leaves, a mix of half-clover-like cotyledons (seed leaves) and miniature arugula leaves, were so intertwined that I couldn't distinguish which seedling was which, and had to decide which seedlings to keep based on location and stem thickness. I had to remove several seedlings at a time to clear just an inch between the remaining seedlings. Every time I cut a stem, the smell of fresh arugula, of mustard and pepper, was released. The resulting row was more zig-zag than straight line, and the remaining arugula seedlings looked a bit wobbly surrounded by all that open space. But, given a couple weeks of sun and water, those wobbly seedlings will have grown together, and will once again need thinning.
The reward for thinning seedlings was a fresh salad of greens straight from the garden. Bigger than sprouts but still much smaller than baby greens, two-sets-of-leaves seedlings offer the crunch and water content of sprouts with a bit of the taste and substance of salad greens. I eat seedling salads with just a touch of olive oil, salt, and cracked pepper. I don't use heavy or flavorful salad dressings because I want to enjoy the flavors of the greens themselves, the spice of the Asian greens, the pepper of arugula, the earthiness of beets and chard, and the occasional hint of sweet from a few lettuce seedlings. Hints of cool-season flavors to come.