Well, the seeds I started almost three weeks ago are full-fledged seedlings now. They’re the plant equivalents of toddlers. No longer content to stay where I put them, they’re declaring their newfound independence by straining towards the sun.
All of them have true leaves now—not just those run-of-the-mill round or oblong cotyledons that first break through the soil, but those highly varied second leaves, the ones that are beginning to betray the personality of the mature plant. They may have lobes, teeth, interesting vein patterns, or, most intoxicating of all, scent. The first true leaves of my Holy basil plants are about five eighths of an inch long, and the other morning I couldn’t resist gently rubbing one of them between my fingertips. I brought my fingers to my nose, inhaled, and almost swooned. These plants smell exactly as Southern Exposure’s seed catalog promised: “a spicy scent of clove, lemon, and cinnamon.” It’s more exotic than the smell of any other plant I’ve grown in my garden. How nice to know this early in the season that I’ve found an absolute keeper! This one, I predict, will be a staple of years to come. (And there’s still plenty of time for you to start some of your own!)
Now that the herbs, onions, and brassicas are up and growing, I figured it would be a good time to talk about taking care of seedlings. Seedlings—like all plants—need water, light, and nutrients. Let’s take these one at a time.
First, water. You want the soil to stay damp but not soaked. This can usually be accomplished by watering lightly once a day. The morning is usually the best time for this, as the sun will quickly warm the soil and water and prevent any chill. I always keep water in bottles beside my plants, for two reasons. One, it’s good to have the water at room temperature. Plants don’t like the shock of super-cold water (or super-hot water, for that matter). Two, if you always have water at the ready, you’ll be much more likely to give your plants a refresher when they need it. And on very warm, sunny days, they probably will need an extra drink in the early afternoon.
Now light. This might be the hardest part of starting seedlings indoors. If you have a greenhouse, of course, you’re all set. But if you don’t have a greenhouse, you need to find a south-facing window (if you’re in the northern hemisphere). Vegetable plants do best in full sun, which means direct sun for six or more hours a day. Even in a south-facing window, you’re not going to get that many hours of direct sunlight in February, so in the mornings, I start my plants in an east-facing window and then move them to the south around noon. Obviously you will have to work with the windows available to you. If you have no south-facing windows, I’m not sure what to tell you. Some people have apparently had success with fluorescent grow lights (see this post at Trying to Find the Good Life), but when I tried this several years ago, the results were abysmal. Tall, skinny, floppy seedlings. Tall and skinny seedlings are the best indication that your plants are not getting enough light. They’re growing taller thinking maybe they’re being shaded by other plants, and if they can just get above them, maybe they’ll have a chance. Have pity on them and find them more direct sun!
One thing I do to increase the light shining on my plants (and keep them from constantly pressing their faces to the window like nosy next-door neighbors) is to use reflectors. These are just panels of cardboard that I’ve covered with aluminum foil. I glue the foil on with Elmer’s glue diluted with a little water to make it spreadable with a paint brush. Propped up behind the plants, these reflectors probably give the plants 50% more light. They’re especially useful on cloudy days. And on really brilliantly sunny days, I sometimes leave them off to keep the seedlings from getting burnt to a crisp. (These are the same panels that I use for my solar cooker, so I know they’re pretty effective…)
Now, nutrients. Hopefully you put some fertilizer into your soil mix. This alone will be sufficient, but if you want to speed your seedlings up a little, you can add something more. What you need is a liquid fertilizer. This can be a little tricky to do organically. Apparently it’s really, really difficult to get organic phosphorus to dissolve in water. So I have a confession to make. This is the one area in which I’m not organic. I use Miracle-Gro. It’s just so cheap and easy, and since I only use it for a very limited time and on very limited amounts of soil, I consider that it’s going to do more good than harm. I also use it in very dilute concentrations: one third of the strength recommended on the package. And I only apply this every other day, in place of my regular watering. It’s very important not to overdo fertilizer. You can burn the poor plants and actually end up retarding their growth.
One final thing. If you planted more than one seed per pot (as I hope you did, since some of them aren’t going to germinate, and of those that do, some may “damp off”—wither once they get to the seedling stage), you’re probably going to need to thin the plants as they get bigger. Do this gradually. When they get their first true leaves, use scissors to snip off all but the healthiest two plants. (It’s best not to pull the plants out of the soil, because you risk disturbing the roots of the other seedlings.) When the third true leaf appears, snip off another of the seedlings, leaving the best to grow on. In this way, you’ll consistently get the healthiest plants from your lot of seeds!
If you’ve planted some seeds in flats, like onions, you’ll probably need to thin those seedlings as well, so they’re not growing right up against each other. They should be pencil width by the time you plant them into the garden, so allow them at least that much space and then some. I’m still experimenting with onions myself. If anyone has suggestions on a good final spacing for onion seedlings, please suggest away!
Now go get your plants some light!