Seed starting does not need to be intimidating but it does come with a special set of requirements for true success. Two components to that success are the soils we use and the containers we choose. Not all soils and containers are created equal. Today we dig into the different types of seed starting mediums and containers available on the market and ones we can dig up in our own home. (Pun intended.) Ssurprise surprise, the potting soil you choose to use may not actually be soil at all. And the containers may be something you already have sitting in your recycling bin. Let’s dig in!
*February Question of the Month: What is your most successful crop and why?
Episode References and Resources
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This is positively farming media.
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Last week we talked specifically about starting flower seeds
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indoors and I mentioned that the process for starting annual
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flowers is pretty similar to what we do with our annual
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vegetable plants. Seed starting does not need to
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be intimidating, but it does come with a special set of
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requirements for true success. 2 components to that success are
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the soils we use and the containers we choose.
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Not all soils and containers are created equal, so today on Just
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Grow Something, we're going to dig into the different types of
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seed starting mediums and containers available on the
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market and ones we can dig up in our own home.
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Pun intended. And surprise, surprise, the
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potting soil you choose may just not actually be soil at all, and
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the containers may be something you already have sitting in your
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recycling bin. Let's dig in.
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Hey, I'm Karen. I started gardening in a small
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corner of my suburban backyard and now 18 years later, I've got
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a degree in horticulture and operate a 40 acre market farm.
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I believe there is power in food and that everyone should know
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how to grow at least a little bit of their own.
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On this podcast I share evidence based techniques to help you
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plant, grow, harvest, and store all your family's favorites.
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Consider me your friend in the garden.
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So grab your garden journal and a cup of coffee and get ready to
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just grow something. So don't forget to answer the
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February question of the month. What is your most successful
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crop and why? This could be a specific variety
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of something that just out produces all the others.
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The plant that you love the most, or the crop that grows
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fantastically well for you without fail every single year.
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Whatever you consider your most successful crop, in whatever way
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you consider it successful, send me an e-mail, post it in the
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Facebook group, or send me Adm on Facebook, Instagram, tiktok,
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wherever You have until February 29th to get me your answer.
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Now, for some of us, seeds starting is exciting and for
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others it might be a little, well, terrifying.
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I love starting seeds indoors because it lets me get my hands
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dirty and get some sort of garden activity going well
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before it's warm enough to be doing anything outside in the
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gardens. And it's a bit of a necessity
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for most gardeners if they want to take full advantage of
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whatever growing season they have.
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Starting seeds indoors gives us the ability to get those plants
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to a more mature state before moving them out into the garden.
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And we sort of cheat Mother Nature by getting to grow things
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that may not be native to our area.
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If I were to start broccoli seeds outside in the soil, I
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would never get a head of broccoli.
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By the time the soil is warm enough to get those seeds to
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germinate, we are so far into our spring that in just a few
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weeks the air temperatures are likely to cause the plants to
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bolt and just go to seed. So we start them indoors 6 to 8
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weeks before our last anticipated frost in the spring,
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and then move them outside when the soil temperatures are warm
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enough to sustain the plant, but the air temperatures aren't
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threatening to become too warm. Same thing goes for warm weather
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crops, especially in areas with short summer growing seasons.
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If you're in an area with only 80 frost free days, you can't
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possibly wait to start your tomato or your pepper seeds
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outdoors, because by the time the soils are warm enough for
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those seeds to germinate, you'll likely only have like 60 days
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left to garden before the 1st frost.
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Not nearly enough time to get a crop.
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So most beginning gardeners will turn to purchasing started
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plants from their local nursery, the garden center, or the
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farmer's market. We sell a ton of started
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seedlings every single spring at the farmer's market, but if you
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have a really big garden and you need a lot of started plants,
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this can get expensive. I figured that out really
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quickly when we started the farm.
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It was one thing for me to buy plants when I was growing just
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for our family, but when it became a business, I needed a
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lot more plants and the cost quickly became prohibitive.
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The main things you need when starting your own seeds indoors
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are a seed starting mix of some sort containers to put it in
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light, heat and air. And we'll talk about those last
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three things next week. For right now, let's focus on
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the first two, beginning with seed starting mix.
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Seed starting mixes are specifically formulated to
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provide the ideal conditions for germination and early seedling
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growth. They are typically soil less
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mixes composed of a combination of materials like peat Moss,
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vermiculite, perlite and coconut quart.
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These materials are lightweight, well draining and sterile,
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reducing the risk of soil borne diseases and providing a loose,
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airy structure for young roots to penetrate easily.
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Seed starting mixes are free from pathogens and weed seeds,
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ensuring a clean environment for seed germination.
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They retain moisture well while still allowing for proper
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aeration, promoting healthy root development.
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Their lightweight nature makes them easy to work with and
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allows for better drainage, reducing the risk of over
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watering and damping off both common problems.
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In indoor seed starting. Some seed starting mixes may
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contain peat Moss which does have an environmental impact.
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So when choosing a medium that contains peat Moss, pay
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attention to where the Moss is being sourced.
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In fact, the sale of peat Moss in England will actually be
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banned starting this year because of those environmental
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concerns. I prefer Canadian peat Moss
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because their regulators do a really good job of only allowing
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a certain percentage of virgin bogs to be touched each year,
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and they require the companies to do remediation when they do.
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It's a bit more sustainable, but if you can stick to alternate
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components like coconut Kwar, then that's even better.
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We do need to be aware that seed starting mixes typically lack
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any nutrients. The seeds don't need any extra
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nutrients when they're sprouting.
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They have it all within their tiny little seed coat.
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Remember, a seed is just a baby plant in a little package with a
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sack lunch full of nutrients. But they'll eat up all those
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nutrients, pushing their way out of that little package and up
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through the soil. So if you use a soil less seed
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starting mix, the seedlings will need to be fertilized in some
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way once they develop their first true leaves.
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Now using garden soil for seed starting is not recommended for
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several reasons. Garden soil is just heavy and it
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may contain weed seeds or pathogens or even insect pests
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that can harm our little seedlings.
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It also lacks the proper structure and drainage needed
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for successful seed germination and the early growth of those
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seedlings, because it tends to compact once it's removed from
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the garden and placed into a container.
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If you've ever pulled a plant, roots and all, from the garden
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and put it into a pot, you've noticed that after some time
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that garden soil begins to settle down into the container
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that hinders root growth and oxygen exchange.
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And it's not what we want our little seedlings to be dealing
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with while they're trying to get big and strong and get ready to
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go outside. Garden soil by itself in a
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container also tends to retain too much moisture or just drain
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really poorly, which also increases the risk of seed rot
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and fungal disease. So don't just go out and dig up
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some soil from your garden and try to start your seeds in it.
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So if we don't want to use regular old garden soil, what
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about all-purpose potting soil? Why not use that for starting
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our seeds indoors? Traditional potting mixes are
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suitable for established plants, but they're not really ideal for
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seed starting. These mixes often contain soil
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ingredients like compost or topsoil or other organic matter
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which can be too heavy and dense for the little delicate seeds
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and seedlings. They may not provide the correct
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balance of moisture retention and drainage that's needed for
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successful seed germination. They may also introduce
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pathogens into the Sealy environment because they do
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contain a soil component which of course increases the risk of
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disease. With that being said, I actually
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do use an all-purpose potting soil as my seed starting medium.
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I have used many, many different brands of potting soils over the
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years and I will say 90% of them or more.
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We're absolutely not suited for seed starting.
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The brand I use now is Pro Mix and I've found it is the perfect
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texture. It's well draining, it doesn't
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compact, and it has just enough nutrients in it that I don't
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need to feed my plants weekly until they are well on their way
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to being hardened off and ready to go out in the garden.
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If you have a potting soil that you use regularly to pot up
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larger plants, run your fingers through the mix to see if it
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might be suitable for your seed starting.
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It should feel light and airy. It shouldn't contain any really
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large chunks of soil or pieces of wood or anything else for
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that matter. I was desperate a couple of
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years ago because my supplier ran out of pro mix and I had to
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opt for something else. And I will tell you, I was
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horrified by what came out of that bag.
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I wasn't even using it for seed starting at that point.
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This was for transplants, but those transplants didn't stand a
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chance. They didn't grow, they were
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super stunted, Their roots didn't develop.
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It was it was horrible. I've also had potting mix in the
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past that had a lot of sand in it.
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Too much sand, which was fine for my transplants but would
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have been a horrible choice for seed starting.
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So if you're a beginner or you've not had great luck
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starting your own seeds indoors in the past, I would absolutely
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stick to a soil less seed starting mix to start with.
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There are lots of brands out there to choose from.
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Burpee Espoma back to the roots. Jiffy Gardner Supply.
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Find something that speaks to you.
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They're all going to do the job. Oh and Speaking of Jiffy, there
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is another soil less medium that I sort of failed to mention and
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that is Pete Pellets or Coconut Quar pellets.
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These are little netted discs and they contain either peat or
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Coco quart and they expand up when you add water and then you
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pop the seed in the top and it's like a little stand alone
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seedling pot and medium all in one.
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I've used the ones that are made from coconut quart for starting
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lettuce seeds and then I transferred those into a
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hydroponic setup and I was actually really impressed.
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But you can also just pop them right out into the garden.
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Again, this is an inert medium, so you will need to feed those
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seedlings once they've sprout. And you'll need to house those
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expanded pellets in a tray of some sort so that you can water
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them. I prefer to water them from the
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bottom. This is a really good way to do
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that. This would be similar to
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starting in soil blocks, and they didn't really know whether
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to consider soil blocks a seed starting medium or a container
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because like these cocoa pellets, soil blocks are both
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the container and the starting medium.
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The difference with soil blocks is you are creating a starting
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medium yourself, either by choosing to use a potting soil
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like my pro mix or by creating your own.
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Which brings me to creating your own seed starting mix.
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If you've been doing this for a while, yes, you can mix your own
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ingredients if you want to. This might be a good option for
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you if you're starting a lot of seeds and if you can buy the
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components of that mix for less expensively than what you would
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pay for a bagged mix. There are a lot of different
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recipe variations out there for creating your own seed starting
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medium. The basic components are one
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part water retention material, one part drainage material, and
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one or two parts of a substrate to hold it all together and
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allow the roots to grow. Vermiculite is usually used for
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water retention. Vermiculite is a type of
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silicate mined from rocks. The pieces are heated at very
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high temperatures in order to expand them and then the gold
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colored Nuggets are very effective at holding water, then
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slowly releasing it to the plants as the medium dries out.
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This also means once you start feeding your seedlings, the
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remiculite is also retaining any liquid nutrients to deliver to
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the plant roots gradually. It does provide some structure
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for aeration, but not as well as our next component.
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Perlite is typically the ingredient used for drainage.
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Perlite is made from mined volcanic rock or glass and is
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also heated under extreme temperatures until it puffs into
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a tiny white ball that looks a bit like Styrofoam.
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These pieces create air pockets within the seed starting medium
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to allow water to drain and roots to move.
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What you choose to use as the remaining substrate is up to
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you. Many recipes will call for one
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part compost, but as we've already discussed, compost,
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especially homemade compost, can contain pathogens your little
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seedlings will have to fight. Peat Moss is typically the other
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recommendation, but if we're trying to avoid using that,
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Coconut koir, finely shredded pine bark, and pit Moss, a
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recycled paper product designed to replace peat Moss, are all
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good options. Use a combination of these to
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get the proper texture for your seed starting mix.
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You might also see worm castings used in some recipes, and while
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it's fine to use some worm castings as part of the
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components, you don't want to use too much.
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Worm castings are typically very finely textured and they can
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retain moisture, both things that may throw off the texture
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of your mix. If using worm castings, be sure
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it only accounts for about 1/2 of one part of the mixture.
00:14:13
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00:15:53
so we've covered seed starting mixes.
00:15:56
Now what do you put it in? We want something that's going
00:16:00
to be big enough for the plants that we're starting to reside in
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for the first few weeks of growth.
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We don't want to have to pot up seedlings too early in their
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life cycle, so avoid things that are small or shallow.
00:16:13
Unless it's a small or shallow rooted plant, there are plenty
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of options out there to purchase like seedling flats and seed
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starting kits with domes and they all get the job done.
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It just depends on how much you want to spend and how much
00:16:27
plastic you want to deal with because most of these are made
00:16:30
out of plastic. And remember, these things
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likely will need to be stored somewhere until you use them
00:16:36
again next season, and unless they're designed to be reused,
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they will likely breakdown over time.
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If you want to avoid the plastic altogether, then you can either
00:16:46
make your own soil blocks or use those coconut core pucks we
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talked about. Otherwise, there are plenty of
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options using repurposed or recycled items you may already
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have laying around the house or in your recycling bin.
00:17:01
For shallow rooted plants like lettuces, try egg cartoons.
00:17:05
Each egg cup serves as an individual container.
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If you use the Styrofoam ones, you'll need to pull the seedling
00:17:11
out and transplant it, but if you use the cardboard ones, you
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can just cut the carton up into the individual cells.
00:17:17
When you're ready to transplant, just cut a split in the bottom
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to open it up a little bit and pop the whole thing down into
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the ground. I used egg cartoons for several
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years when I first started seeds, and as a bonus you've got
00:17:30
a ready made lid to close and trap in the moisture while
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you're waiting for those seeds to sprout.
00:17:35
Other items that you can recycle into containers include
00:17:39
individual yogurt cups or larger yogurt or cottage cheese tubs,
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salad containers or clam shells. That fruit comes in again with
00:17:47
the bonus that they have their own lids to trap the moisture.
00:17:51
Milk cartoons, milk jugs or two liter bottles.
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Cut the tops off about halfway down and fill it with the seed
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starting mix and then again you can have a lid that traps the
00:18:00
moisture while you wait for the seeds to sprout.
00:18:02
Same thing with foil roasting pans or lasagna pans.
00:18:06
These can be used just like a seed starting flat you would buy
00:18:09
online, but if it has one of those clear plastic lids with
00:18:13
it, you also have a little mini greenhouse for your started
00:18:15
seeds. You can get really creative and
00:18:19
use the empty cardboard tubes from the center of toilet paper
00:18:23
or paper towel rolls. Just fold one end together to
00:18:26
create a flat bottom to hold the soil or use newspaper folded
00:18:31
into a paper pot. There are tutorials online to
00:18:34
show you how to do this and it's a great way to reuse something
00:18:37
you already have. And I'll bet if you've gardened
00:18:40
before and purchased plants from the nursery, you likely have
00:18:44
some old nursery containers sitting around.
00:18:46
There is absolutely nothing wrong with cleaning those
00:18:48
containers with some hot soapy water and reusing them to start
00:18:52
your seeds. Seed starting does not need to
00:18:57
be complicated and it shouldn't be expensive.
00:18:59
We're trying to save money, so buy or make the best seed
00:19:03
starting mix you can and don't worry about the fancy
00:19:06
containers. Use what you have available
00:19:08
available to you. The next week, we're going to
00:19:10
talk about the options for heat, light, and air flow.
00:19:13
Combined with what we talked about today, you should have a
00:19:16
good idea of where to start with the supplies that you'll need to
00:19:20
get started with starting your own seats.
00:19:22
Until next time, my gardening friends.
00:19:24
Keep on cultivating that dream garden and we'll talk again
00:19:26
soon. Thanks for listening to another
00:19:29
episode of the Just Grow Something podcast.
00:19:31
For more information about today's topic and to find all
00:19:34
the ways you can get in touch with me or support the show, go
00:19:37
to justgrowsomethingpodcast.com. Until next time, my gardening
00:19:41
friends keep learning and keep growing.