How to: Starting Spring Seedlings
Ostara’s a great time to start seedlings in our growing zone (#6), and by the time Beltane rolls around, they’re hardy enough to survive outdoors. (Don’t know your growing zone? Check here.)
Our 2022 indoor seedlings include:
Tomatoes—Roma, yellow, and grape
Peppers—Tangerine Dream, hot banana, and poblanos
Brussels sprouts
Herbs—dill and loads of basil
Flowers—calendula, marigolds, and nasturtiums
The flowers and basil provide natural pest control when mixed in with the veggies. The rest of our crops have either wintered over (i.e.: parsley, mint, sage, strawberries, raspberries, asparagus) or will be direct planted at Beltane (i.e.: beans, peas, cucumbers, beets, spinach, lettuce, carrots). We’re also allowing some red potatoes to grow eyes in preparation for planting.
Steps to start your spring seedlings (as with all things, have your intention fully in mind before starting):
Gather your supplies. (I’ve added links below to the items we have purchased and used. If you purchase from an Amazon link, be aware that we will receive a small percentage of your purchase.)
Soil pucks (a.k.a. “peat pellets”) and growing trays—You’ll have to buy new pucks every year, but the trays can be reused over and over until they fall apart. (peat pellets, growing trays)
Seed starter fertilizer—I use Burpee organic, but there are loads of options out there, so pick your favorite. (seed starter fertilizer)
Seeds—You can buy what you need from most garden centers, order online, or grab what you need from your refrigerator or pantry (this works especially well with things like tomatoes, peppers, and potatoes). When buying seeds, I’m a Burpee fan both thanks to their line of non-GMO and organic seeds and I always get a high germination rate. Pick the one that speaks to you. Be sure to save seeds in the fall so you won’t have to buy next year. (Burpee)
Timer—You can go crazy on expense with these or just pick up something really simple and inexpensive like the one in the above photo. (timers)
Heating mat—For me, this is where to spend a little extra money. Be sure you’re getting something waterproof and temperature-controlled, so it doesn’t overheat your seedlings or short out. (large heating mat, small heating mat)
Grow lights—If you have a window that gets all-day sun, you may not need added UV, but if you’re like us, your plants may need a little boost. Find something that will cover all your seedlings without draining your power bills. LED lights have fit the bill for us—they use less power, don’t get as hot, and still provide quality UV to the plants. (clip-on grow light, grow light with stand, hanging grow light)
Table—You’ll need to set aside a space for at least six weeks. We use a card table and fill the empty spaces with old yogurt containers, so the cats don’t sit on our seedling trays. (large folding table)
Decide how many pucks you’ll need. I generally overplant by about 30 percent. That way, if a seedling dies, I have backups. If I wind up with too many plants, my neighbors are always happy to take them off my hands.
Place the pucks in the trays and soak them. Let your seedling fertilizer soak in the water for 10 to 15 minutes first then pour into the tray. Tray styles vary, but the ones we use have holes between the pucks. Pour the water in the holes instead of directly on the soil pucks for best results. Allow them to sit and absorb for about an hour. Add more if needed.
CAUTION: Do not over-soak the pucks as it will suffocate your seeds. The pucks should be puffed up and moist but not shiny and dripping—the soil should flake, not roll up into mud-balls when you touch it.
Set up a chart (or some other way to identify which seedlings are where). I’ve labeled the rows and columns of the tray and work with that as a grid, but you might have better option. (One year, I used craft sticks to delineate between groups.) I fill in the chart as I plant, but you can fill it out before or after—whatever works best for you.
Fluff the soil. Using an old fork, toothpicks, craft sticks or whatever works for you, lightly loosen the soil on the top of each puck to give your seeds some breathing room as they germinate.
Sow the seeds. Place one seed in the middle of each puck and lightly cover them with a small amount of the fluffed soil. Like too much water will suffocate the seedlings, too much soil or too hard-packed soil can make it difficult for them to send out shoots.
Cover and wait. Place the lids on the trays, trays on the heating mat, and arrange the grow lights to cover the whole spread. I use the heating mat with the timer, but my lights have to be manually turned on and off daily.
Feed, water and tend.
Only leave the heating mat and grow lights on for a few hours a day—akin to what the seeds would receive if they were outdoors. I go with eight-ish hours. Too much heat will cause your seedlings to get “leggy,” or grow overly long and weak stems. Too much light will cause their leaves to yellow.
Water them when the soil looks dry. As with the initial soak, use the tray’s holes to water don’t overwater or you risk suffocating the baby plants.
Remove the tray lids for three to four hours a day to let them breathe. Watch for white mold—it looks like fuzzy or spider webs—as it means that your seedlings are too wet. Scrape it off gently, leave the lids off longer to allow the area to dry out, and water less frequently.
As the seedlings grow taller, switch to a taller lid to allow them space to grow.
As they get their first true leaves (the ones that actually look like plant your growing—the set they sprout with are called cotyledon leaves), move your seedlings to larger pots. You can buy biodegradable ones that will allow you to plant the whole pot outside, reusable plastic ones, or recycle old food containers. This gives them more room to grow.
Use a low-powered electric fan on them for an hour or two daily once they sprout. This emulates outdoor wind and makes their stems stronger.
