How to start from seed

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I’ve got a lot of seeds I haven’t used up from the past two or three years, and I promised myself I wouldn’t buy more until I’ve used what I’ve got.

However, for each year a seed is saved, its germination rate goes way down. For example, I have some commercial celery seeds from three years ago that might not sprout at all. I’m also starting some pepper seeds I saved myself two years ago, another pepper from Seed Savers last year, and some lavender I picked up at a chain hardware store this spring (I have trouble remembering to be disciplined when it comes to gardening shit).

With such a variety of ages and sources, there’s no telling what will make it to harvest, especially with the older seeds. But it’s either throw them away or throw them in dirt to see what happens. Here’s my general plan of attack for starting anything from seed:

1. Find out how early the seed needs to be started indoors.

The celery, peppers, and lavender I’m working with all need roughly eight to 10 weeks’ head start before my area’s last frost date. That’s the date I can reasonably expect there will be no more frost that could kill my young plants. In Omaha, Neb., the last frost date is May 10. Counting back from there, I figure out that these seeds need to get started in early March.

The seed packets usually tell you how much start time they need, but I check that against a couple of my favorite gardening books and maybe a Google search too. Veggies are like dogs — everyone’s got an opinion on how to work with ’em.


2. Collect your supplies.

You will need:

  • Your seeds. Obvs.
  • More potting soil than you think. I typically keep a 50lb bag around. It never goes to waste.
  • A seed tray, definitely with a clear plastic cover and preferably with a heating mat to go underneath. Your seeds will be slower to start without that extra, gentle heat.
  • A spray bottle of water. Save the watering can for grown-up plants.
  • Something to poke holes in dirt. I like to use a wooden kebab, but pencils, pens, etc. all work.
  • A light source for after the seeds have germinated. If you don’t have good natural light for a few hours, get a grow light.
  • Stickers and a marker for labeling the edge of the tray. No, you will not remember how many cells are bell peppers and how many are Thai chilis in two months.

3. Prep the seed tray.

Don’t try to fill each cell in the seed tray individually. You’ll get annoyed. Dump a bunch of potting soil in the middle of the tray and scrape the dirt into the cells. Don’t pack them down yet, just fill them like you would a cup of flour.


With every cell filled, spray down the tray with your water bottle. Much, much easier and cleaner than trying to pour water over these shallow trays. Anyway, you want to achieve “just barely soaking,” not “drowning.” If some cells look shallower than others now, fill in with a bit more potting soil.


4. Plant your seeds!

The depth you plant your seeds depends on the size of the seed. Celery seeds are beyond tiny, so they just get sprinkled right on the surface of the soil. Another spritz with water, a tiny bit of packing with your fingertip, and those are “planted.”

Pepper seeds are a bit bigger and go about 1/4″ below the surface. My stars, do not bother to measure. Take your poking stick and make a small, shallow hole in the cell.


Pop a couple seeds into each cell, three if your seeds are older than a year. Germination rate, remember? We don’t want to waste space on dead seeds. If more than one plant starts to grow in a cell, choose the strongest looking seedling and carefully pull out the other one. Thinning, baby, it’s harsh.


Lightly pack the soil over the seeds, topping off shallow cells with more soil if necessary. Finish with another spritz of water, pop the cover on the tray, and set the tray on its warming pad. YOU HAVE PLANTED.

5. Don’t forget to maintain them.

These trays are shallow, and you never want to drown them with too much water, so they can dry out quickly. Check on them every day and plan to spritz the trays at least every other day.

It’ll be a couple weeks before you see any growth, but when you do, take the lid off immediately. Too much humidity can cause damping off, and your seedlings need the extra light anyway. I’ve got my plants near some great windows, but make sure yours have at least a grow light close over them if nothing else.

There you go! You’re on your way to raising your very own garden right from the very beginning!

What’d I miss? Any other tips for starting from seed out there?

Comments on How to start from seed

  1. I found some flat plastic trays to put under my seed cells. After the seeds germinate, you can just water them all at once by pouring water onto the tray! I also learned from trial and error to cut apart the seed cells into groups of six or so and to plant the same type or seedlings with similar growth rates. That way you can set your grow lamp to the highest seedlings, and place books under the trays for the shorties to keep them all 3 inches or so away from the lamp so they don’t get leggy. Also I try to remember to hit them with a fan for a couple minutes a day to encourage strong growth. But the good thing is that you don’t HAVE to do these things!

  2. So, let’s just pretend for a minute that I am completely green-things-ignorant. Why do you need to start seedlings indoors? Why can’t you just plant them outside? How do these things grow naturally if this isn’t a possibility? I just don’t understand. 🙁

    • Starting seedlings indoors makes for a more hardy plant when it moves outdoors. Plus, you reduce the risk of bugs/birds eating your seeds. You get a few weeks to baby the seedlings, and have them develop good root systems.

    • The short answer is that not all plants can grow naturally in all parts of the world. Many vegetables would only grow naturally and produce in the warmer climates. The growing season (time between spring and fall frosts) for the northern climates is too short. If you plant seed outdoors, you have to wait till much later when the dangers of frost are over. Starting indoors gives the plant anywhere from 6-10 weeks more time to mature and produce before the fall frosts. Example: tomatoes need soil temperatures of about 75* F to germinate. I have had volunteer tomato plants that started from the seed of a missed tomato the prior year. However, there was not enough time left in the growing season for the plant to actually produce tomatoes before the fall frosts killed it.

      • “Natural” native plants in an area have the ability to start in the ground right where they are. As Sarah B pointed out, though, they don’t really produce a ton of veggies before the autumn frost–they don’t need to! They just want to spread their seeds, and a couple little tomatoes will get that job done just fine.
        Because most people want bigger vegetables and more of ’em, they use seeds that have been cultivated to make plants that produce big veg in big quantities. There’s almost always a tradeoff in what a particular plant is capable of–most plants focus on production, size and taste above hardiness, as most gardeners accept that tending plants is just part of the deal.
        And bear in mind that a lot of the veggies that people want are actually native to places with longer summers–almost all peppers in the world started from plants found in Central America, so they’re used to starting the year in much warmer soil and spending the whole season in heat and sunshine. To get any result at all from the plant, you’ve got to replicate that, at least a little.
        But if you pay attention to your seed packets, some can totally be started in the ground in your zone. My parents always start lettuce in the ground, which has a short grow time.

  3. Great timing, I just started some of my seeds on Sun night! It is still very cold and snowy here in CT, but I am beyond excited to get the garden started this spring. Am hoping to get the soil prepped and turned over in the next few weeks.
    One of my favorite tips my father gave me: soak your seeds in water for a day or two before planting. It gives them a great head start. (especially when your growing season runs short like it does here in New England)

    • Absolutely — there are also a few seeds out there that require a bit of extra lovin’ in other ways. Nasturtiums, for example, can benefit from taking an emery board to that tough husk before planting. Not 100% necessary, but helps them get out of the ground that much more quickly!

  4. Thanks for this article! I started a tiny garden at my library last fall & seeds have been the bane of my existence. Even when using brand new seeds last fall I only got about a third of my plants to germinate. The spray bottle tip is genius! Here is a helpful tip in return (or maybe it’s common knowledge & I’m just plant ignorant) the lady who was helping me from the local ag extension told me you plant your seeds twice as deep as the size of the seed. So really little seeds just need to be covered with a little bit of dirt!

    • that depends highly on the kinds of plants you’re buying whether it will be worth it to seed save.

      Many non-organic raised plants will produce seeds, but they are infertile by design to force you to buy them again next year from the “manufacturer” — many of your local, large home improvement stores have this kind. If you buy the organic, or even just open pollinated if organic is too much, you have a much better shot at getting good seeds for the next year.

      For best cost over generations, I’d see about local seed savers exchanges and seed libraries. I’m in New England and there’s a few up here I’ve been wanting to just buy their entire selection and be that guy in my neighborhood.

      I would agree that seeing a “how to seed save” come late Summer/early Fall would be faboo, though. I just want to make sure it’s worth your time to put in the effort, given how readily available the shootin’ blanks guys are.

    • I definitely save seeds where I can! Tomatoes, squash, and corn for example are stupid easy to save. And I usually just buy my potatoes, uh, at the grocery store. Don’t forget to let a few heads of lettuce go to seed late in the year too — I’ve already got volunteers popping up. Ha, stay tuned for September 😉

  5. If you have trouble with figuring out when to start your seeds (I have about 20 different kinds of plants to work with this year), this seed starting calculator is a boon:

    Also, if you’re cheap like me, you can start your seeds in biodegradable egg cartons instead of splashing out for a tray. Bonus: you can plant each egg section straight in the ground/pot when you’re ready to transplant. I also re-use the plastic containers I buy my organic salad greens in- lids become water trays that I set my egg cartons on, and the container itself becomes a mini-greenhouse to provide extra warmth/humidity (and protection from my curios cat!) for the seeds. Yeah repurposing!

  6. Do you have any advice for those of us living in apartments, but wanting to start a small indoor garden? I would love to do vegetables, but I know that’s unrealistic. I was, however, thinking I could grow herbs indoors and use them for cooking. I’d also like to try flowers, if possible, but one thing at a time. 🙂

    • I just planted 5 little pots of herbs using the same method she posted here. I’m lucky enough to have a porch so I’ll be able to put them out during the day but I’ll still have to bring them in at night, I think.

      I planted chives, thyme, cilantro, oregano, lemon balm, and lavender just because I got a pack of the seeds from someone. Here’s hoping!!!

    • I definitely got my gardening start with herbs. They’re very forgiving, and don’t need pollination like veg do. But if you’ve got a balcony, GIRL. Get a tomato plant in a bucket or something out there. It’ll happen, and it’s SO FUN. Same with strawberries!

  7. Just a thought about thinning seedlings started in small cells. I find pulling them up, can disturb the ones I want to keep, so I use a small pair of scissors and just clip off the non-keepers. If its a veggie, the cutting can be eaten! The root adds to the organic matter in the soil.

  8. So I’m starting herb seeds for indoor container planting. Do I really *need* a heating pad and light? Because I’m not planting them outside I don’t really mind how long they take. It was sunny last week and I had a few seedlings pop up, they still look healthy but I have noticed a growth slowdown now that its overcast.

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