Seed starting is one of my favorite farm tasks. Watching a tiny seed germinate, leaf out, and flourish in the garden is quite magical. We sometimes buy starts if we just want one or two of a common plant, but for a staggering selection of varieties, and to have enough to share with friends, sowing your own seeds is key. Here’s how we do it.
Step 1: Right Plant, Right Time
Different plants need different growing conditions, and therefore should be sown at different times. Some seeds, like corn, are best direct sown in the ground outside. But many things can be started inside, while it’s still snowing, to get a head start on the harvest. Seed packets will tell you what’s best for each variety, based on your last frost date. If you’re planting more than a few things, or you want to sow every few weeks for a successive harvest, try to create a seeding schedule to keep everything on track.
Step 2: Gather Your Supplies
Here at Lunaria, we like to keep it sustainable… and cheap. That means we try to find resuse old items instead of buying new things. Of course, you can buy all of these things at any garden store.
Containers: There are many different options for containers, from plastic pots to egg cartons to beer cups from last night’s kegger, even soil blocks that use no container at all. What ever you use, just make sure it has some drainage holes in the bottom. If water can’t drain, your beautiful plant roots will drown and the seedling will quickly perish.
Soil Mix: Some gardeners swear by a sterile, soilless mix of peat moss and vermiculite, while others wouldn’t use anything but rich compost. After experimenting with different mixes this year, I’m personally a partial to a balanced native soil. If you don’t feel like guessing, you can buy a bag of potting mix and relax.
Watering Trays: You’ll want to do much of your watering from below to prevent the dreaded “damping off” (more about that soon). We use old baking sheets and plastic bins, but anything that can hold your pots and water will do the trick. Soil will wick water up through capillary action, but you can also use a capillary mat with one side under your pots and the other end in a container of water. They sell fancy ones at stores but you can use any scrap of natural fabric, like a towel, jeans, wool felt, or blanket.
Light Source: We’re making do with a south-facing window because they’re located in the kitchen where we often have the light on at night and on cloudy days. But ideally your seedlings should have more light than that. Without enough light, plants become leggy – thin, spindly, struggling things. Give your plants a good start and offer plenty of light for at least 12 hours per day. They don’t need special grow lights, any florescent or incandescent bulb covering a wide area will do. Make sure you don’t burn your plants with a light placed too close; you can raise it as the plants grow.
Seeds: There are endless sources for seed out there, and seed patent technology is a lucrative business, indeed. Many commercial seed companies sell F1 hybrids, which take advantage of “hybrid vigor” to be unfailingly productive and uniform, but will not breed true if you try to save seeds. Saving seeds from patented varieties may also be illegal! If you want to collect seeds from plants that will carry on genes specific to your growing conditions, make sure you select open pollinated varieties. All heirloom varieties are open pollinated, as they were selected and bred for flavor and regional uniqueness instead of uniformity and shipability. Seed Savers Exchange was founded to save endangered varieties from extinction. Selecting organic seed will ensure that your seeds are not genetically modified. Try to choose a local company, because your seeds are more likely to be adapted to your growing region. The only thing better than buying local is trading with fellow gardeners! Mail your friends packets and give handfuls to neighbors. When you save your own, there’s always some to share.
Plant tags: My all-time favorite tagging method is a popsicle stick with the variety name and sowing date written in Sharpie. Whatever you use, make sure it can stand up to being wet.
Step 3: Sowing
Put the soil mix is in the pots within a half inch of the top, tamp down slightly, and water (overhead watering is fine). Figure out how deep the seed needs to be planted. It will say on the packet, but, as a rule, 2 – 3 times the width of the seed is good. Put a dimple in the soil to that depth, and drop your seeds in. Some gardeners sow a few seeds in each hole and thin to the strongest seedling. I personally think that wastes a lot of seed so I plant one seed to each pot, but plant more many pots than I need, and just remove the ones that haven’t germinated after a while. Inevitably, some seedlings won’t make it, and its nice to have extras for gifts, so make sure to oversow. Once your seed is in there, cover it up with a little bit of soil, and tamp it down a little. Soil contact is important for good germination, but you don’t want to compress the soil. Tag your seed so you know what’s what, and relax for a little while. Most seeds don’t need light to germinate, and although warm conditions can speed germination, we keep our seeds at room temperature.
Step 4: Tend your sprouts
Hopefully you’ve been keeping your seeds well-watered, and if conditions are right, within a week or so you should see little sprouts with a set of cotyledons, their baby leaves. Congratulations! But once you see them germinate, lay off the H2O a little and make sure they receive good ventilation. Maintaining drier conditions is the best defense against damping off, a general fungal rot that is the biggest killer of seedlings. Keeping the soil line way at the top of your container is one way to promote good airflow, in addition to turning a fan on or opening the windows. That little bit of wind will strengthen your little sprouts’ stems, and prepare them for the outside world. Water from the bottom now that they’ve come up, until the soil is moist, not wet. Let them dry out a bit between waterings, and sit back and watch your babies grow.
Seedlings have all the food they need for a little while, so there’s no need to give them extra nutrients. Fertilizing this young can harm your plants. But once you see true leaves, your seedlings are in active phosynthesizing mode. Now it’s okay to give them compost or other fertilizer high in nitrogen or potassium to promote healthy leaf and root growth. It’s also safe to move them, either into a bigger pot, the cold frame, or outside in the garden.
We’ll have another post on transplanting soon. Until then, you can check out Hudson Valley Seed Library’s blog. They have a great 6-part series called Seed Starting 101.