Seed Starting Indoors

Hi friends! One of the first signs of Spring for me is when I get to start seeds indoors. My dining room gets taken over by Solo cups filled with soil and seeds for 2 months, but it’s a daily reminder that Spring (and Summer!) are on their way! When I first started gardening, seed starting seemed to be a very mystical and complicated process. But now that I have a few years of it under my belt, it’s really pretty easy and straight forward.

I live in Zone 7, so if I mention specific times I started, know what I’m basing it off of. But, you should follow specific guidelines for your own zone, depending on where you live. The most important thing to base seed starting on is your last frost.

What are these Zones, anyways?

Keep hearing and reading about garden zones, but have no idea what people are talking about? I didn’t either. But, zones are actually a very helpful way for you to help plan when you’re going to start your garden. They help you determine what plants you can plant in your garden to have your seeds grow and thrive, as well as when to start planning certain seeds and plants. Zones are based on annual moisture, altitude, type of terrain and typical temperature extremes.

garden zone map
Such a helpful map and pretty picture from the National Gardening Association!

If you don’t know your zone, or want to learn more about the zoning system, check out the National Gardening Association’s article and updated zoning maps. You can just type your ZIP code in on their website, and they’ll tell you exactly what zone you’re in!

What Seeds Should I Start Indoors?

Some seeds do better sown directly into the soil, while others prefer being started in warmer weather. I learned from my dad that you always start peppers and tomatoes from seeds indoors. They take a long time to grow, so for us in the Mid-Atlantic, you need to start them before they will grow outside if you want tomatoes or peppers before the fall. Peppers and tomatoes are also sensitive to transferring from container to the garden, so it’s nice to have small plants (instead of seedlings) to transfer into your native soil, so they’re a little hardier.

If you want early spring spinach or lettuce, you can start both in a container indoors. They grow to maturity pretty quickly–45-60 days–so you if you start lettuce now, you can have lettuce and spinach to eat mid May from your containers. I normally grow some in containers and grow another few rows directly in the garden soil.

I’ve tried starting other vegetables inside and it’s been hit or miss for me. Cucumbers, spaghetti squash, zucchini, peas–some years they’ve done great starting indoors and some years they die as soon as I put them in soil. This year, I’m going to try them all directly from soil. I’ll keep you posted as they season goes on!

Supplies

You don’t need much to start your garden indoors. Here’s what I use every year:

  • Soil, specific for seed starting or potted plants. I love Miracle Gro’s Nature’s Care Organic & Natural Potting Mix, which you can buy at any Home Depot. It uses natural fertilizers to help nourish your seeds without adding chemicals.
  • Pots or cups.
  • Seeds- I use Burpee Seeds exclusively. They have such a large selection of seeds, shipping for seeds is always only $2.99, and a couple times a year, have a great BOGO sale!
  • Old newspaper or cardboard box lid.
  • Drill if your pots or cups aren’t perforated with drainage holes.
  • Sharpie or blank labels.

As you get more experienced with seed starting, you may want to invest in some fancy equipment, such as heating mats to help keep your seeds warm and germinate faster, and grow lamps to provide more consistent light for your seedlings. We don’t have a ton of space in our house for a separate corner for seed starting right now, but if you have some space (and don’t want to lose your dining room for 2 months like I do), they may be worth looking into.

Step 1: Pick Your Spot

The best spot for your seeds (if you’re not using a lamp or a heating pad to keep them warm) is a warm spot with a lot of bright sunlight. Our dining room is the perfect spot in our house–it has two windows to place seedlings in that get sunlight most the day and there are heating vents right below each window to keep the seedlings warm.

Unfortunately, since we start a bunch of peppers indoors, that means putting some family pictures and other decorations away for 2 months while they’re growing. If we had a warmer spot in the basement, or a bigger house, I’d pick another spot, but that’s the only place that meets the sunny and warm criteria.

So, to prepare yourself, make sure you clean out anything that needs to be stored for a few months, and I lay newspaper down to protect the surface. Your goal is to keep the space clean from soil and excess water dripping. I’ve also used box tops and cookie trays in the past and they work perfectly.

Step 2: Prep Your Pots

If you you’re using a seed starting kit, your containers should already have drainage holes in the bottom (and they may even have soil and fertilizer in them). If so, skip to the next step!

If you’re using your own pots (or cups or something else creative), make sure there’s a few drainage holes in the bottom so that excess water runs out, and your soil doesn’t stay wet and breed mold. I use solo cups and any extra plastic pots for plants purchased in previous years. Just make sure to wash them with soap and water and let them dry before using this year, in case there’s any disease lingering from last year’s plants.

To make drainage holes, the easiest way is to take your drill and simply drill 3 holes in each cup at the base. I make a sort of triangle at the base to allow for equal drainage.

If you don’t have a drill, you could try poking holes through with something sharp, like a screwdriver, but I won’t promise how well that’ll work since I didn’t try it 🙂

Once you’ve prepped your pots, add your soil. You should make sure to get a soil specifically for fruits and vegetables, or even better, specifically for seed starting. These often have extra nutrients included to feed the seeds, as well as provide some moisture control. I fill my pots to 1″ from the top, so when the seedlings sprout they can reach the sun when they’re little.

Step 3: Plant Seeds

For whatever seeds you’re planting, make sure you read the instructions on the packaging for how deep to plant them.

For peppers, they tend to need to be planted about 1/2″ (or the top of your finger) below the surface. I stick the top of my finger in to the first knuckle, pull it out, and then put 2-3 seeds in. Then gently cover them with soil–that’s it! And, make sure you label your pots with what’s in them. If you have 15 kinds of peppers, you want to know which plant is which, so you know what you like and don’t like, or what worked and what didn’t when you go to harvest in the fall and also order seeds next year.

Why plant more than one seed?

Not all seeds will actually live to germinate (grow), so to hedge your bets, it’s a good idea to put 2-3 seeds in per pot. If none grow, make sure you’re not overwatering or it isn’t too cold of a spot (basically, try again and pay attention to these things). If it doesn’t work again, your seeds may be bad. If they all grow, then you’ll thin them out and see if you can get all three to grow later down the road.

I prepped these pots for the lettuce and spinach outside so I didn’t make a gigantic mess inside.

For lettuce and spinach, they need to be right below the surface of the soil. So, my dad taught me to run my finger in a long line down the center of the pot. I use a long rectangular flower pot for these. Then sprinkle the seeds straight from the package from one end of the row to the other. After that, just gently cover the seeds with soil and you’re set!

Step 4: Water

Make sure you gently water your seeds. You want to water them so the soil is damp, but not soaked. And, if you see a bunch of water come out your drainage holes in the next day, you know that was too much for the next time you water.

After the first watering, I check my pots every day and water when the soil is dry to the touch. If you over-water or under-water, your seeds can die, so it’s important to stay on top of it. I usually have to water 2-3 times per week, depending on how sunny it is.

Step 5: Place in Sunny, Warm Spot and Wait

And so, the long wait begins. If you’re starting lettuce or spinach, you’ll see sprouts in a few days! I make sure to rotate my pots every few days because you’ll see the sprouts start leaning towards the sun.

For the peppers, sometimes it takes 3 weeks for seedlings to emerge, so it’s a real long wait. Just keep babying your seeds and keep your fingers crossed!

Do seeds really need light?

During this time when you’re growing seeds, they don’t need sunlight (there’s nothing outside of the soil to soak up those rays!). So, if you have a warm spot without light somewhere else in your house, feel free to start them there. Just make sure you move them to a sunny spot as soon as the seeds start to emerge, so those seedlings get all the light and nutrients they need.

This is my last picture for this year! I’ll update the post with more pics as the season progresses.

Step 6: Thin Out Seedlings

Once you have seedlings (woohoo!!!), you may be lucky enough to have had a few of your seeds germinate and grow into seedlings. If you have more than one seedling per pot, you’ll need to thin them out before they get too big. I usually wait until there’s two sets of leaves on the seedlings to make sure they have enough root to be able to move them and have them reestablish in a new pot.

When separating the seedlings, you need to be very gentle to not break their roots, which are probably intertwined. Once you separate them, make a hole the size of the root in a new pot, and plant one of the seedlings in the new pot and replant one in your old pot. Make sure you use the same soil in the new pot so the seedling isn’t too shocked by its new home.

Step 7: Watch Your Seeds Grow

Now you just sit back and watch your seeds grow! Make sure you stay on top of watering them, but otherwise you’re just waiting for them to be hardy enough to have the best success for transplanting outside (and for the weather to be nice enough for them to survive outside).

Step 8: Get Your Seedlings Used to the Outdoors

A few weeks before I think I’m going to transplant the seedlings, I start putting them outside during the day to start getting used to things like wind, outdoor sun strength, and even rain. Think about it–you’ve basically been coddling your seedlings for weeks, but the indoor environment is not reality for them. They need to start building up their strength and tolerance for their permanent home.

I typically start putting the seeds outside for an hour, then 2, then 4, etc until they’ve spent most of their day outside. I also typically start with a cloudy or partly sunny, warm day, and as I get further along in the process and the seedlings get stronger, add in a rainy day or windy day or hot day or cold day (not freezing mind you, but maybe 60 degrees when our typical summer days are 85).

You may see them wilt or bend a little. If that’s the case, bring them back inside and baby them for a few more days until they perk up. Then start the process again.

My very first community garden plot in 2016, right after planting my seeds and pepper plants.

Step 9: Transplant Outdoors When it’s Time

Once your seedlings start to look little plants (have a pretty strong central stalk, have more than 2 sets of leaves), they should be big enough to survive outside.

When the weather is right (i.e. there’s no chance for frost) and your plants have had a few weeks to start getting hardy in for a few hours a day, I leave my plants outside overnight for a few nights as a last and final test.

Then after checking the weather to make sure we’re not expecting a hurricane or other torrential wind or rain storm, I plan on planting my seeds in their permanent homes.

Dig a hole the size of the cup (or pot) and squeeze your plant out gently from your cup. Then make sure the soil around the roots is loose (and the roots themselves) are loose, and plant your plant in the ground. Gently pat the dirt/soil around the plant and water. I typically water directly at the base of the plant for a few seconds until the ground is saturated.

Make sure you are checking on your soil a couple times a week, to see if your plants need watering. Once they get a little older, they’ll be much more tolerant to a few forgotten watering’s or over-watering, but it’s a good idea to baby them for the time being.

A few tips on transplanting:

Sometimes your plants don’t like going from super nutrient-rich potting soil to your regular dirt (part of what can cause transplant shock). To help prevent this, my dad taught me to mix some extra potting soil into the spot where you’re going to transplant the seedlings, so the first thing these baby roots grow through is a mixture of natural dirt and potting soil. So, it’s not quite a shock to the system as just straight natural dirt.

Another thing you can do is put a little plant food (fertilizer) and mix it into the soil before planting. This will give your baby plant an immediate food source to help stimulate growth.

That same garden 2 months later!

Last Few Thoughts

I think the most important thing I’ve learned from seed starting (and gardening in general) is that it really is a mix of care and luck.

You definitely will reap more fruits and vegetables if you weed your garden, water it regularly, and feed the plants a few times over the summer.

But, you can also follow all the guides and instructions you want, and that pepper plant you babied for months still doesn’t grow peppers.

On the flip side, you can completely ignore your zucchini for 2 months and it’ll grow the most zucchinis of any plant you have.

Just one week’s harvest from my garden last July

Another important lesson is there’s nothing wrong with a little trial and error. Maybe your backyard soil isn’t conducive to a certain type of tomato, or your climate is too wet for your dream hot peppers. Try a few on one side of your garden, a few in a different spot, one in a container, and see what does best! Then, write it down so next year you remember what worked best and you’ll get more crops!

I hope this post inspired you to start some seeds to get ready for the growing season! I’ll add pictures to the steps as I reach them in my house this spring. Comment below if you have any questions!

Happy growing!

~Lauren

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