How To Start Seeds Indoors For The Best Tomatoes Ever

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Starting Tomatoes from Seed

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I am excited to be able to introduce you to Kathi from Oak Hill Homestead!

I have been starting tomatoes from seed for several years now. Because.  Flavor and variety.  Sometimes I order an obscene amount of tomato seeds. And I can never get enough 😉

Once you have gotten a feel for starting your own you will be hooked. And there is something so satisfying about transplanting a tomato plant you grew from seed! Starting tomato seeds can be a little daunting at first but Kathi makes it so clear and easy, you will be able to begin with confidence!

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This post is part of the Series: Your Best Garden Ever!




This is an amazing source for a variety of beautiful, tasty, heirloom varieties.

Seeds for Generations is a family owned, quality seed company. How to grow pumpkins successfulluy. gardening beginners

Without further rambling on:

Here's Kathi!

I am obsessed with tomatoes. Not just any tomato though, no, I love fresh-from-the-garden tomatoes with the flavor of sunshine on a summer day.

So I'm waiting very impatiently for spring to arrive and for summer to bring me the most flavorful, beautiful tomatoes. And you know that the freshest tomatoes I can find will be the ones ripening in my own garden. If you're reading this, I'm betting you too will be growing your own delicious tomatoes in your garden or in containers.

For many years I bought tomato transplants from local businesses, but as I've gained confidence in my gardening skills I've been growing my own plants from seed. This allows me to try varieties that aren't available as transplants.

If you've ever looked in a seed catalog or website, you've likely been overwhelmed by the choices available. How do you know which tomato varieties to order? Even a seed display at the local feed store will have a number of varieties from which to choose. Here's how to make an informed choice.



Starting Tomatoes From Seed: Considerations

Determinate vs indeterminate

Determinate varieties will only grow so big - usually around three feet tall - then stop growing and concentrate on producing fruit. If you're planning to can tomatoes, determinate plants will give you a large harvest at once which is convenient for canning. Varieties known as “patio tomatoes” are usually determinate plants as well.

Indeterminate tomato varieties grow all season long. They will set fruit continually, so you'll have ripe tomatoes all summer. Indeterminate varieties need to be staked or trellised.

Size and color of the fruit

Beefsteak tomatoes are the largest, while salad tomatoes and slicing tomatoes are medium-sized. Cherry and grape tomatoes are the smallest, just right for popping in your mouth while you're weeding the tomato patch.

Tomatoes come in yellow, orange, pink, brown, black, green and purple varieties, and maybe a few more colors that I haven't mentioned. You can even find striped tomatoes.

Disease resistance

Some areas are prone to tomato diseases. If this is a problem in your area, choose seeds that are disease-resistant. They will be marked with a "V" (for verticillium) or "F" (for fusarium) after the name of the variety in catalogs.

Your growing season

Lastly, you'll want to choose your tomato seeds based on your growing season. Here in Oklahoma, our growing season is long, so I don't need to even think about this one. My daughter who lives in the Rockies must choose tomatoes that ripen early because her growing season is so short.


Starting Tomatoes From Seeds: Instructions

When to start tomato seeds

Tomato seeds are generally started indoors and transplanted to the garden after the last frost in spring. To find your ideal seed-starting date, use this handy calculator from Dave's Garden. Just enter your zip code in the box and click the red button to find the date of your last average frost.

Count back 6 to 8 weeks from this date to find your seed-starting date. Planting your seeds this early allows plenty of time for them to germinate, grow at least two sets of leaves, and be hardened off so they can be transplanted to the garden after the last frost.


Step by Step


Getting Prepped

The most important aspect of seed starting is to use clean pots or trays and sterile seed starting mix. Potting mix is generally too heavy to use to start seeds.

Wash previously-used containers well before filling and planting. You can use just about anything that will hold soil but poke a hole in the bottom to allow excess water to escape. Fill the container with seed-starting medium to about 1/2" from the top. Press the seed-starting mix down lightly. Moisten the seed-starting mix, but not so much that it's soaking wet.



Place your seeds on top of the planting mix, allowing 2-3 seeds per pot, and cover with about 1/4" of additional planting medium, firming it gently down.

Moisten the top layer of the pot so your seed will have good contact with the soil, using a mister or spray bottle.

I sprinkle cinnamon powder on top of my seed starting mix to discourage bacteria, which thrives in moist, humid conditions. Sprinkling a thin layer of sand, sphagnum moss or perlite on the surface will also help to prevent bacteria and fungi.



Caring for your seedlings

Put your pots in a warm place, between 75° and 80°F. Light isn't necessary at this point. Cover the pots with plastic wrap or use the plastic cover for your seed flat.

Check your seeds daily and mist them with water when needed. Tomato seeds sprout in about 6-14 days depending on the variety.

As soon as your seeds sprout, remove the plastic wrap or cover and move the pots to a sunny window. Rotate the plants daily so they grow evenly. Using grow lights is a better option if you have them. Keep the lights just an inch or two above the tops of the plants for good strong growth.

Run a fan in the room with your seedlings to keep the air dry and prevent fungus. Keep your plants watered by using a mister, spray bottle, or set the pots in a tray of water and allow the water to wick up to the roots.



Continuing Care

As your plants continue to grow, you'll need to thin the seedlings so there is just one plant in each pot. Choose the strongest seedling and cut the others off at ground level with scissors. Don't pull the seedlings out of the soil, as this will disturb the roots of the plant you want to keep.

Your grow lights should be about 3-6" inches above the tops of the plants. Check daily and move the lights higher as needed. If your plants are in a windowsill, continue to rotate them daily to keep them from bending toward the sunlight.

When your plants have their second set of "true leaves" - don't count the first tiny leaves that sprouted, but the next two sets of leaves - they’ll benefit from a light fertilizing with a water-soluble fertilizer. (Comfrey tea is an excellent natural fertilizer you can make yourself.)

When your tomato plants need more room for their roots to grow, gently move them to larger containers. Soon it will be time to harden them off and plant them outdoors. Enjoy those garden-ripe tomatoes!

Why would you want to start your tomatoes from seed when you can buy them already started? The varieties are endless when you start your own plants from seed, and with that comes tremendous flavor! This guide takes all the guesswork out of the process of starting your own tomato seeds indoors!

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About the Author:

Kathi Rogers


Kathi believes we're never too old to learn. Follow her at Oak Hill Homestead where she'll inspire you to live a simple, abundant life by teaching you how to "do stuff."




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  1. Pingback: Your Best Garden Ever! A Garden Series To Give You All The Tools You Need To Succeed - BeanpostFarmstead

  2. I love starting my own seeds from scratch! I have grown so many interesting heirloom tomatoes that just aren’t available as starts at the garden centers.

    Last year I started: Rutgers, Tigerella, Moonglow, Trucker’s Favorite, Reisentraube, yellow pear, Amish paste, Roma, and Oxheart.

    I need to get busy and go through all of my seeds to see if I need more tomatoes! Thanks for the reminder. 🙂

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