I've been gardening and writing about gardening for more than 20 years, yet I find I'm always learning new things about the plants, insects and other critters that call my backyard home. That's the great thing about gardening &#; it's never boring! I've worked as a landscaper, on an organic farm, as a research technician in a plant pathology lab and ran a small cut-flower business, all of which inform my garden writing. Someone once asked me when I'll be finished with my gardens, to which I replied, "Never!" For me, gardening is a process, not a goal.
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A seed-starting kit, such as theA seed-starting kit, such as the GrowEase Seed Starter Kit , makes it easy to grow vigorous, healthy seedlings.
I've talked to so many gardeners who are experienced at growing plants outdoors but hesitate to start seeds indoors. To me, starting seeds is one of the most rewarding parts of gardening. It gets my hands in the soil (or at least the seed-starting mix) during the dark, cold days of late winter and early spring. And it's so amazing and rewarding to plant a seemingly lifeless seed and watch it sprout and grow. Here are answers to some of the hundreds of questions I've been asked about seed starting. When you see how easy it is, I hope you'll give it a try!
Grow a dozen or more plants from a single packet of seeds.Grow a dozen or more plants from a single packet of seeds.
Gardeners start their own seeds for all sorts of reasons. First of all, if you start your own seeds, you can plant hard-to-find varieties. You'll likely find fewer than a dozen varieties available as plants at your local garden center, but hundreds more are available as seeds.You can save money, too; a packet of seeds costs a few dollars and usually contains a dozen or more seeds &#; a single plant often costs more than an entire packet. Nurturing a little patch of green indoors is a great way to beat the winter blues, and I think it's particularly rewarding to grow a plant from seed to harvest.
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Zinnias are one of the easiest flowers to grow from seed.Zinnias are one of the easiest flowers to grow from seed.
If you're new to seed starting, begin with easy, reliable seeds, including tomato, pepper, basil, zinnia, marigold, cosmos. These all germinate readily and grow quickly. Once you've mastered these, you can try your hand at more challenging plants.
Most seed packets include sowing instructions.Most seed packets include sowing instructions.
When you're starting seeds indoors, timing is everything. The goal is to grow seedlings that are the ideal size for transplanting into the garden at the proper time. Sowing dates depend on:
Most seed packets suggest a planting time, such as "sow seeds indoors six weeks before your average last frost date." To calculate your planting date, start by determining your average last spring frost date, mark it on a calendar, and count back in one-week increments.
Related Article: When to Start Your Seeds
Create a planting calendar by counting back from your last frost date.Create a planting calendar by counting back from your last frost date.
The easiest way to find out is to ask a neighbor who's an experienced gardener or ask staff at your local garden center. You can also visit The Old Farmer's Almanac website or find a Master Gardener program (part of your state's Cooperative Extension). The date of the actual last spring frost varies from year to year so the "average last spring frost date" is just an approximation, but it gives you a starting point.
Growing on a windowsill, these sad-looking seedlings are reaching for the light.Growing on a windowsill, these sad-looking seedlings are reaching for the light.
Although it's possible to grow seedlings on a sunny windowsill, you'll get much better results if you grow them under lights. That's because the sunlight in early spring isn't nearly as intense as summer sun, and the days are shorter, too. Seedlings growing on a windowsill will reach for the sun, resulting in long, weak stems that bend toward the light. Plants grown under the consistent, bright fluorescent lights of a light garden, on the other hand, will have strong, stocky stems that will adapt better once they're transplanted into the garden.
Related Article: How To Garden With Grow Lights
Seed-starting mixes are well-drained and disease-free.Seed-starting mixes are well-drained and disease-free.
Garden soil tends to drain poorly, especially when it's used in small seed-starting trays. It can also harbor disease organisms that can damage or kill young seedlings. You'll get the best results by starting seeds in a mix formulated for starting seeds indoors, such as our exclusive Organic Seed Starting Mix.
Related Article: Choosing the Right Soil for Seed Starting
Seed-starting systems are designed for healthy seedling growth.Seed-starting systems are designed for healthy seedling growth.
Although you can start seeds in any container that has drainage holes, specially designed seed-starting pots and trays provide optimal conditions. They let you start lots of seeds in a small space, and they drain freely to prevent rot. Some people prefer biodegradable pots; others prefer reusable trays. Self-watering, all-in-one seed-starting systems are convenient and foolproof.
Related Article: Our Seed Starting Buying Guide
Basil, pepper and zinnia seeds: different sizes, different planting depths.Basil, pepper and zinnia seeds: different sizes, different planting depths.
Most seed packets tell you how deep to plant. A rule of thumb is to sow seeds two or three times as deep as they are wide. Take care not to plant seeds too deep. A seed contains a limited supply of stored food to nourish it during germination. If you plant it too deep, it will run out of food before it reaches the light and grows big enough to start producing its own. Some seeds require light to germinate; the seed packet should say this. Sow these seeds on the surface of the planting mix.
Self-watering seed starters take the guesswork out of watering.Self-watering seed starters take the guesswork out of watering.
Bottom watering is usually preferable because it keeps the soil surface dryer, helping prevent disease problems. For small seeds or surface-sown seeds, top misting keeps the surface moist for better germination. Self-watering seed-starting systems, such as our GrowEase Seed Starter Kit, use a wicking fabric to supply water from the bottom, providing a steady supply of just the right amount of water to plant roots. You just fill the reservoir and don't need to worry about over- or under-watering.
Remove the greenhouse cover as soon as you see the first shoots.Remove the greenhouse cover as soon as you see the first shoots.
The greenhouse cover holds in moisture, raising the humidity for fast germination. As soon as you see the first tiny sprout, remove the cover. This allows air to circulate around seedlings, minimizing disease problems.
Keep lights 4" to 6" above the seedlings.Keep lights 4" to 6" above the seedlings.
Keep the lights a few inches from the tops of the seedlings to promote strong, stocky growth. Our grow light stands have adjustable lights that are easy to raise as the seedlings grow.
A seed starting timer makes it easy to give plants the proper amount of light.Most seedlings grow best when lights are kept on for about 14 to 16 hours per day. They need a period of darkness (as they would in nature) to rest and prepare for active growth when the lights are back on. An automatic timer makes this easy.
Thin seedlings to one per cell.Thin seedlings to one per cell.
A few weeks after seeds start growing, they may start crowding each other. When that happens, it will be time to thin the seedlings. This is the hardest part of seed starting for most gardeners. Choose the strongest seedling and removing the others nearby. This gives the remaining seedling room to grow. Although you can try to separate seedlings and replant, invariably you'll damage some roots, setting back growth. The best way to thin is to snip off extra seedlings at the soil line.
"True leaves" resemble the plant's mature leaves."True leaves" resemble the plant's mature leaves.
The first set of leaf-like structures aren't leaves at all, but are the seed's food storage structures, called cotyledons. The second and subsequent sets are true leaves, and they resemble the mature plant's leaves. Begin fertilizing seedlings when they're an inch or two tall, or when they have their second set of true leaves.
Time to transplant &#; before the roots get too crowded.Time to transplant &#; before the roots get too crowded.
Tomatoes and other fast-growing plants may outgrow their pots before it's time to move them into the garden. About a month after sowing or when seedlings are about 4" tall, gently remove one of the seedlings from its pot. If the roots are beginning to fill the space, then it's time to transplant them into a larger pot. Avoid waiting too long, because root crowding can stunt plant growth and make it difficult for plants to recover after transplanting. Our Pop Out Pots are ideal transplant pots.
Acclimate seedlings before planting them in the garden.Acclimate seedlings before planting them in the garden.
Hardening off is simply acclimating plants to outdoor conditions. Seedlings grown indoors have been coddled &#; you've been giving them just the right amount of light, moisture and nutrients. Outdoor conditions are more challenging, with fluctuating temperatures and light levels, more variable soil moisture, and wind. About a week before you plan to set the seedlings into the garden, start hardening them off. Place them in a protected spot outdoors (partly shaded, out of the wind) for a few hours, bringing them in at night. Gradually, over the course of a week or 10 days, expose them to more and more sunshine and wind. A cold frame is a great place to harden off plants.
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Even the most experienced seed starters occasionally have problems. Here are some symptoms, and possible causes.
Poor germination. Although most common vegetables and annual flowers germinate readily, some types of plants have notoriously poor germination rates. Often, this is indicated on the seed packet (with the suggestion to sow extra seed). First of all, be sure you've given plants enough time to germinate. At sowing time, mark the pots with the type of plant, date of sowing, and days to germination (found on the seed packet). Some seeds take two weeks or more to sprout. Poor germination can be caused by overly wet or cold soil, which causes seeds to rot. (The latter can be remedied with a Heat Mat.) If the soil was too dry, the seeds may not have been able to absorb enough moisture to sprout. And if the soil dried out even once after they began growing, the fragile new roots may have died before the shoot even emerged above the soil. Poor germination can also be caused by out-dated seed, and seed that hasn't been properly stored.
Damping off. If, after a few days, some of your seedlings keel over, as though a tiny lumberjack felled them at the soil line, then you're probably seeing the effects of damping off. This is caused by soil-borne fungi attacking the stem. There's no cure, and the seeds won't resprout. Start over with clean containers and sterile seed-starting mix. Allow the soil surface to dry out slightly between waterings, and place a fan in the room for good air circulation. To disinfect used containers, sterilize them in a 10 percent bleach solution (1 part bleach to 9 parts water.) To learn more, read the article Damping Off.
Mold and algae growth. If you see fuzzy white growth or slimy green patches on the surface of the planting mix, or on the outside of biodegradable pots, it's probably mold or algae. Although generally harmless to the seedling, they both indicate that the seed-starting mix is too wet. Allow it to dry out slightly between waterings and use a small fan in the room to increase air circulation.
Pale, stretched-out seedlings with weak stems. "Leggy" seedlings are often the result of inadequate light, both in intensity and duration. Place plants under grow lights, arranging them so the lights are a few inches above the tops of the plants, and keep the lights on for about 14 to 16 hours per day. Leggy plants can also result from too-warm room temperatures and overcrowding. Inadequate fertilizing can lead to pale, weak-stemmed plants.
Discolored leaves. If seedling foliage is pale green, yellowish green, or has a purple cast to it, the plants may need a nutrient boost. Begin fertilizing seedlings when they're an inch or two tall, or when they have their second set of true leaves. Use a water-soluble fertilizer that's diluted to half-strength, applying weekly for the first few weeks. After that, you can go up to full strength applied weekly. (Be sure to follow the label directions for dilution rates.)
Exactly as the title says&#;this is an easy, no-fail guide to indoor seed starting.
You don&#;t need to read any gardening books first. You don&#;t need any fancy equipment. You just need your seeds (these are the best garden seed catalogs that I order from every year) and a few basic supplies to get started.
Whether you have a dedicated vegetable bed in your backyard, or a cluster of containers on your patio, it all starts out the same way. You have to plant your seeds, and germinating seeds inside your home (where you have the most control) is the best way to do so, especially for seeds that are hard to start.
Starting seeds indoors is ideal if you want to get a head start on the season, or if the weather is still too hot or too cold to put anything in the ground.
Related: How to find your first and last frost dates so you don&#;t plant too early (or too late)&#;my custom planting calendar included!
This simple step-by-step tutorial will take you from seed to seedling with a minimum of fuss. Just the stuff you need to know, and none that you don&#;t. (But if you&#;re the really-need-to-know type, I&#;ve added footnotes at the end to explain why you&#;re doing what you&#;re doing.)
Disclosure: If you shop from my article or make a purchase through one of my links, I may receive commissions on some of the products I recommend.
If you&#;ve already made your recycled newspaper pots, you&#;re all set. If you&#;ll be using other seed starting pots or cell trays, make sure they&#;re clean. (1)
You can also repurpose household items into seed starting containers, like egg cartons, Dixie cups, and yogurt cups. Just wash them out and poke a few drainage holes in the bottom with a nail or an awl.
Dump your seed starting mix into a large tub or bucket, pour in a generous amount of water, and stir it up with your hands or a trowel.
As the seed starting mix starts to absorb the moisture, add more water as needed. (This will take several minutes, as peat-based seed starting mixes are slow to absorb.) You want the mix to be uniformly damp, like wet sand.
Fill your pots or trays with this pre-moistened seed starting mix. (2)
Place two to four seeds (per pot) on the surface of the seed starting mix, and gently press the seeds down with your fingers so they&#;re nestled in nicely.
If your seeds are very small, like basil or mustard, you can leave them uncovered. (3)
For more information, please visit Leak-Proof Seedling Trays.
If your seeds are larger (like beans or peas) or they require darkness to germinate (check the instructions on the seed packets), cover them with a layer of vermiculite or seed starting mix equal to their height, usually 1/4 inch to 1/2 inch.
Label each pot. Trust me, you will never remember what you planted where, as most seedlings look the same at birth.
At this early stage, cheap plastic plant markers work great and stay out of the way, so save your big and beautiful metal plant markers for the garden.
Mist your seeds with water. (4)
Assemble your pots in a propagation tray (or repurpose a disposable aluminum roasting pan or baking pan) and cover with a humidity dome (or just plain old plastic wrap). (5)
If your dome has vents, keep them open to help with air circulation during the sprouting period.
Now, you need to add heat. Since sunlight is not essential at this point, your seed trays can be placed wherever it&#;s warmest in your house, such as an attic, bathroom, laundry room, or kitchen. (6)
If your seedling pots stay covered in a warm nook, the low humidity will keep your seeds happy until they sprout. High humidity will make them sad. Only spritz the seeds with more water if the mix feels dry to the touch. (7)
Within a couple of days to a couple of weeks, the seeds will germinate. As your seedlings start to emerge, some of them will look like they&#;re wearing little seed hats. (No need to do anything, as they&#;ll fall off on their own.)
Germination (the process of a seed sprouting) is highly variable, so don&#;t stress if it feels like it&#;s taking forever to happen. In most cases, seeds will germinate within three weeks (after that, try starting a new round of seeds).
At this stage, the newly germinated seedlings need light. Remove the humidity dome or plastic wrap, and move the seedlings to the sunniest spot in your house (preferably a south-facing window).
Continue to keep the mix moist, but not overly wet. Seedlings should be watered once a day or every other day, depending on how much sun and heat they get.
Remember that seedling roots are fairly close to the surface and they&#;re growing in a small amount of media, so they don&#;t need a deep soak the way larger plants do.
I like using spray bottles or squirt bottles, as the gentle streams of water won&#;t displace seeds or damage seedlings.
After your seedlings develop their first &#;true set&#; of leaves, they are ready to be transplanted. (8)
If more than one seed sprouted (or if you sowed a multigerm seed like chard or beets), choose the strongest one and pinch or snip off the others. You can even keep all of them, but be careful separating the roots if the seedlings are close together.
Transplant the seedling into a larger container filled with potting mix. Hold it by the cotyledons (the first leaves that appeared) and try not to manhandle the tiny roots.
At this stage, you can lightly drench the potting mix using a diluted solution of liquid fertilizer or compost tea. Keep it simple, keep it organic, and don&#;t obsess too much over the nutrients. (9)
Give the seedling plenty of sunlight each day (at least 12 and up to 16 hours is optimal for most vegetable seedlings) to avoid the &#;leggy&#; look. (Learn how to fix leggy seedlings if this is happening to you.) (10)
To get your seedling prepped for a good life outside, you can start to harden off the seedling (11) by moving it outside under diffused light for a few hours and bringing it back inside each night.
Over the next week, move it from diffused sun to partial sun to full sun, and for longer periods of time, until it&#;s finally kept outside all night.
After the hardening off period, you can transplant your seedling to its final destination, whether straight into your garden or into a larger container.
And then, in a couple of months, you can enjoy the fruits (and veggies) of your loving labor!
(1) This seems obvious, but laziness gets the best of us. Clean pots are key and help keep damping off at bay (an untreatable fungal disease that causes seedlings to suddenly keel over and die at the soil line).
Discard or thoroughly wash any pots that previously housed diseased plants. Avoid using leftover soil from the nursery container you brought home, as it might harbor weed seeds and bad bacteria.
If you have a healthy garden, you can skip washing your pots and simply dump out the dirt from your pots before using again.
I&#;ve put countless seed trays and humidity domes to the test over the years, and found these trays and domes to be the thickest and strongest on the market&#;they don&#;t bend, flex, or crack as easily as other brands, and can be reused for many seasons. back
(2) It&#;s easier to start with pre-moistened mix, as peat-based mixes are harder to wet down uniformly if they dry out in pots. Although peat has a very high water-holding capacity once it&#;s wet, it actually repels water when it&#;s dry. Go figure.
If you&#;re not using homemade seed starting mix, this is a reputable brand that I like. If you&#;re looking in a local garden center, you do not need anything fancy; seeds just need a basic mix of perlite, vermiculite, and peat moss (or coco coir) to germinate and grow into healthy seedlings. The cotyledons provide all the nutrients they need for the first week of life. back
(3) For certain types of plants, such as lettuce, light may be necessary for germination (the process of a plant sprouting from a seed). back
(4) The moisture will help the seeds shed their protective coating and eventually sprout. back
(5) This creates a greenhouse effect to keep your seeds moist and warm, the key to germination. Most annual vegetables germinate best in temperatures of 75°F to 90°F. A few, such as radish, will germinate at lower temperatures.
Seeds will sometimes sprout in less than ideal temperatures, but the germination period will be longer. back
(6) I like to put my seed trays next to my heating vent on the floor. Some gardening guides suggest placing your tray on top of a refrigerator, but most appliances these days are energy-efficient and do not give off much heat. back
(7) Too much water will make the seeds rot. If your makeshift greenhouse is looking a bit too wet inside, remove the cover or plastic wrap for a few hours during the warmest part of the day to allow air circulation. Mold is no good for seeds, either. back
(8) The true leaves are actually the second set of leaves that appear; the first leaves that initially unfurl are not leaves at all, but cotyledons. These leaf-life structures are part of the embryo of the seed, and supply food to the seedling until its true leaves begin the process of photosynthesis. back
(9) I like to use a liquid seaweed/fish blend, liquid seaweed, or home-brewed compost tea. No fertilizer is fine, too, especially if you start with good soil. I have grown healthy vegetables with no fertilizer through a whole season, and could barely keep up with the harvests. back
(10) Insufficient light makes your seedling spindly and weak as it channels its energy into growing taller and taller, straining for sunlight. To reduce this problem, I like to gently run my hands across the top of my seedling to simulate a breeze; this slows down initial growth and strengthens the stem. A few brushes a day is all it needs. back
(11) Hardening off is the process of gradually acclimating the seedling to its future environment outdoors&#; getting it acquainted with the breeze, the birds, and the bees. back
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If you're new to seed starting, this foolproof beginner's guide to starting seeds indoors will take you step by step from seed to harvest, quickly and easily.
Prep Time
15 minutes
Active Time
15 minutes
Total Time
30 minutes
Difficulty
Easy
This post updated from an article that originally appeared on March 19, .
If you want to learn more, please visit our website cheap seed starting trays.