Last year was my first year starting plants from seed. I didn’t have a grow light, I didn’t buy seed trays, I tried my hand with the direct sow method in my new garden planters and had mixed success. Direct sowing also meant that I started my growing season later than I really should have. There were a lot of challenges and some successes, but this year I made a decision to start my seeds early and try to do things right.
I invested in a grow light, some seed trays, decent seed starting mix and designated a space to set it up where the seedlings would be protected. I spent a lot of time pouring over website after website, book after book and watched a handful of videos to wrap my head around all the aspects of starting seeds.
Everything I read said pretty much the same thing with few variations. The process really isn’t that hard and, with the exception of the grow lights, not very expensive either. In an hour or two one afternoon you can be completely set up. After that, spending a couple minutes each day to check on the seeds is all it really takes.
The biggest benefit is the jump start on the growing season, allowing you to get started weeks earlier than direct sow. But for me, the biggest joy has been being able to nurture and watch my seeds sprout and grow into my awesome little seedlings. No matter how many times I see it, I still get excited seeing those little sprouts break through the surface of the soil and reach for the light.
In an attempt to make it easier for other people looking to make the leap with growing from seeds, I collected all my research here in one spot in a simple step-by-step format. I also reached out to several experienced growers for their advice, tips and tricks for growing from seed at home.
Step by Step Easy Seed Starting Guide
Pouring through seed catalogs can be overwhelming and exciting. All the great varieties promising a future of abundance. Check out our Seed Selection Q&A for tips on choosing seed for your home garden. Keep in mind that some plants are easier to grow at home than others.
Surefire vegetables include basil, broccoli, brussels sprouts, cabbage, cauliflower, chives, leeks, lettuce, onions, peppers, and tomatoes. Some reliable annual flowers are alyssum, cosmos, marigolds, and zinnias. Perennials include Shasta daisies, columbines, and hollyhocks.
Ultimately, keep it simple. What do you like to eat?
On your mark. Get set. GO!
Timing is everything. Depending on where you live and what your seasons look like, you could have a very tight window for getting things started. Start too soon and you could lose tender plants in a late frost. Start too late and the season may end before you’ve manage to get a decent yield. Determine when the expected Last Frost date is for your area and base your seed starting calendar off of that.
To calculate when to sow your seeds, go to this handy planting calculator from the Old Farmer’s Almanac and enter your zip code. Print it out and you will have a planting plan you can follow through the season.
John Scheepers at Kitchen Garden Seeds recommends getting a jump on the season, “Certain varieties should be started indoors in advance because their days to mature harvest exceed the amount of time between your spring Frost-Free Date and your first fall frost. By starting them indoors, you gain a four to 14 week jump-start on plant development.”
Any container will do
I collect and reuse last year’s nursery flats for just this reason. You can also order seed starting flats online from a number of sources. Otherwise, any clean container 2 or 3 inches deep will do. Punch holes for drainage into the bottom of containers and set them into trays. Protect against plant disease by thoroughly cleaning all used containers: Wash them in hot, soapy water, and rinse with a dilute solution of household bleach and water. If you want a less-irritating substitute for the bleach, use distilled white vinegar.
A tip from PlanetNatural.com, “Plastic containers work better than clay pots when starting seeds, as they retain moisture more consistently.”
Kellie at BackyardRoots.com talks about sanitizing recycled pots “Reusing gardening pots is a great way to save money and be kind to the earth, but it’s important to sanitize your pots in between plantings. This helps reduce the transfer of disease and is especially important if you’re going to be growing seedlings, which are more vulnerable than their adult counterparts. “
Seeds can be a little temperamental about their growing medium. They like a loose, moist, nutrient rich soil that allows for easy root growth. You can buy bags of organic seed-starter mix at your local garden center or you can make your own by blending perlite, vermiculite, and peat. Add 1/4 teaspoon of lime to each gallon of mix to neutralize the acidity of the peat.
You’ll eventually want to repot most of your seedlings into larger containers before setting them into the garden. Some plants like lettuce, melons, and cucumbers are finicky about being transplanted and should go directly from the original containers into the garden. When starting these fussier plants, it can be helpful to add some well-aged, screened compost to your mix to give them a little nutritional boost as they get started. I also like to start these seeds in larger containers (3-4” nursery pots) so they can get better established before their first transplant.
Sow your Seed
Moisten your medium in the containers before sowing the seeds. Next, drop seeds onto the surface of the mix, spacing them as evenly as possible. Cover your seeds to a depth about three times the thickness of the seeds. Some seeds, such as ageratum, alyssum, impatiens, petunias, and snapdragons, should not be covered at all because they need light in order to germinate.
Another suggestion is to lightly sprinkle milled sphagnum moss, a natural fungicide, over everything to protect against damping-off, a fungal disease that rots seeds and seedlings. In the case of seeds that need light to germinate, sprinkle the moss first and then drop the seeds onto the moss.
Try not to handle your seeds any more than necessary. The natural oils from your fingers can damage the seeds and hurt the germination process. It’s best to use a seed sower or carefully sprinkle seed directly from the seed packet without touching them.
Just like in your garden, you’ll want to keep track of which seeds were sown where. When these buggers start popping up, you might not be able to tell your zucchini from your cucumber or your snow peas from your sweet peas. And tomatoes and peppers, forgetaboutit! You can use anything from popsicle sticks to adhesive labels, what matters is accurate labeling.
Warm, wet and happy
Seeds are naturally designed to start the germination process when the right weather conditions present themselves. When starting seed, we need to make sure we are providing them with these ideal conditions or they won’t want to germinate.
Cover your flats with plastic wrap or glass (some come with clear lids) to keep the growing environment humid and place them near a heat vent or on a heat mat made especially for seed starting. Most seeds germinate well at about 70 degrees F.
Stephen Scott at Underwoods Gardens, “Slightly cooler temperatures can double or triple the time needed for germination – even as little as 5°F cooler can be the difference between a 7 day or a 14 day seedling emergence!”
Mist with a spray bottle or set the trays into water so the soil mix wicks up the moisture from below. Watering from below is preferred because it will encourage more root growth.
The germination guide at Terroir Seeds warns, “Uneven moisture levels can seriously delay sprouting of a seed, and even a few minutes lack of moisture as a seedling can kill it, as it has no method of storing water like a mature plant does. During the germination process, a seed needs much more moisture in the soil than when it has sprouted, so be aware and decrease the moisture levels as young seedlings emerge and mature.”
Let there be Light!
Many seeds only need warmth and moisture to germinate, but once they have popped through the surface they’ll be looking for light…and plenty of it.
At the first signs of sprouting, uncover and move your seed starting containers to a bright spot—a sunny window, a greenhouse, or beneath a grow light (more on choosing a grow light). The lights are worthwhile, especially if you live in the North. They provide a steady source of high-intensity light. Short days restrict window light, and your seedlings need 12 to 16 hours of light a day. Suspend the lights just 2 inches above the plants and gradually raise them as the seedlings mature. If plants have to stretch or lean toward the light, they can become weak and spindly. To turn the lights on and off at the same time each day, hook them up to an electric timer.
Seedlings don’t have to stay as warm as germinating seeds. Move them away from radiators and air vents, or off the heating mat, as soon they have germinated.
Some plants like a little more light. John Scheepers writes, “Real warmth-lovers, like Eggplants, Peppers and Tomatoes, like to be coddled with 24-7 grow lights until they become ‘toddlers’ able to handle the cooler, eight hour dark period.”
And there’s always the cost-share option, “Maybe you and another gardening friend or two can combine your seed-starting efforts under one set of grow lights.”
Scot at GottaGrowIt.com has some great information about his Grow Light setup:
Survival of the Fittest
As the seedlings start sprouting up you might have multiple sprouts coming up together. As soon as all of your seeds have germinated it’s time to do some thinning of the herd.
Thin out each pod by snipping all but the healthiest seedling. You may have started 3-5 seeds in each pod, but only one healthy seedling is necessary and overcrowding will affect the health of the seedlings. We want to give them all a chance to live, but your garden wants the fittest of the bunch. Thinning gives your seedlings their best chance for success.
Once the little guys start to grow, they’re gonna get hungry. If you’re using a soilless mix without compost, begin to fertilize your seedlings as soon as they get their first true leaves (the ones that come in after the little, round cotyledon leaves.) Water with a half-strength solution of liquid fish/seaweed fertilizer every week or two. Use either a spray bottle or add the fertilizer to the water you set the trays in if you’re using the wick-up method described above.
You can also dilute a batch of Compost Tea or Compost Extract to feed your seeds. Just don’t overdo it.
Give them some space
Dense planting can cause plants to grow unnaturally tall and slim resulting in a weaker mature plant. Proper spacing is important to give your seedlings room to mature properly. Likewise, a seedling left in a small container too long will result in a bound-up root system that could dwarf the growth of the plant.
If the seedlings outgrow their containers or crowd one another, repot them into larger containers filled with a mix that includes some compost for nutrients. Extract the seedlings carefully with a narrow fork or flat stick, and handle by their leaves and roots to avoid damaging the fragile stems. Don’t worry if some roots are torn in the process, or if most of the potting mix falls away from the roots. Place the seedlings gently into the new pots, and water them to settle the roots.
Place them back into the water trays or put them on a water schedule so the new larger pots don’t dry out.
Ruffle some feathers
Seedlings left to grow inside don’t have a chance to adapt to the elements like their outdoorsy counterparts. As a result, they don’t develop the robust structure they’ll need once they get transplanted outside into the elements. Lightly ruffling seedlings once or twice a day with your hand or a piece of cardboard helps them to grow stocky and strong. Or, set up a small fan to gently, continuously blow on your seedlings. This replicates breezy outdoor conditions and allows the seedlings to adapt early to a more natural environment.
Prepare them for the world
You’ve watched your babies grow from a tiny sprout to a seedling and now it’s time to let it mature into plant-hood. You can’t just kick them out into the cold, dark world. To give them the best chance to survive they’ll have to go through a transition referred to as “hardening off”.
About 1 week before the plants are to go outside, start acclimating them to the harsh conditions of the big world. On a warm spring day move the containers to a shaded, protected place, such as a porch, for a few hours. Each day—unless the weather is horrible—gradually increase the plants’ exposure to sun and breeze. You should also start backing off on the water, allowing the soil to dry out a bit between waterings. At the end of the week leave them out overnight; then transplant them into the garden.
Just do it!
With a little prep and some basic knowledge you can have your seeds going in no time and get an early start on your Spring planting. It makes all the difference in the world to get your seeds off to a good, healthy start in a controlled environment. Treat them well, give them what they need and before you know it you’ll be enjoying the literal fruits of your labor. The only real obstacle is making the decision to do it.
I really enjoyed the process of starting seeds this year and I look forward to continuing the process now that I have a little experience with it. If I can do it, anyone can.
Have any tips to add to this guide? What are your favorite methods, materials or secrets for starting seeds? Tell us in the comments below!