▷ How to Start Tomato Seeds

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How to Start Tomato Seeds

Written by Alan Ray and updated on June 13, 2018
How to start tomato seeds

"Knowledge is knowing that a tomato is a fruit. Wisdom is knowing not to put it in a fruit salad."

-Brian O'Driscoll​

For those folks who can’t wait to get their hands in the dirt, spring not only signals the end of a dreary winter but portends the coming summer months of being outdoors and getting some fresh air and sunshine while gardening to their heart’s content.

And while vegetables of all varieties are being prepped for planting in various and sundry ways by gardeners everywhere, we want to focus on growing that incredibly versatile staple of nearly every home garden, the tomato.

If you enjoy gardening, and especially growing tomatoes, then you understand the excitement the arrival of spring brings for those of us with a love for the outdoors and a green thumb, although admittedly, my thumb runs from light-green to slightly brown at times. Regardless, tomato lovers everywhere, weary of eating store-bought perfectly round, bright red tomatoes with all the flavor of a Dixie cup, realize the time has come to begin growing some real tomatoes!

Starting With Seed

Getting a jump on the season and starting your tomato plants indoors from seed is a great idea for many reasons. If you can start a month or two before planting time that’s great, but even a few weeks beforehand will be beneficial.

When you start with seeds, you have full control over the type of tomatoes you want to grow and are not stuck just growing what is available at your local nursery or garden center. Aside from sheer variety, growing from seed offers other advantages as well.

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Free report shows how to increase your yield

With seed, you can discern which plants are your strongest and most healthy as they grow, while weeding out the weak ones. Another advantage is that by starting with seed, you eliminate the chance of bringing home sick or infected plants and introducing them into your garden. Plants you buy may look healthy but still be carriers and contain microorganisms that can wreak havoc on your healthy plants.

Now that’s not a knock on plant nurseries or other outlets - most are great; it’s just a fact of nature.

Seed Germination

Assuming you’ve chosen your seeds and are ready to get started, let’s look at two approaches to germination.

Many growers like to place one or two seeds into small pots (2-3 inches in diameter) about a half-inch deep, water thoroughly, then place them in a sunny spot. In a few weeks (or sooner) healthy seedlings will emerge. In a few more weeks they will be little plants. Some recommend placing the small pots on a windowsill. Personally, if it’s still cold out, I feel a windowsill’s temperature can drop too drastically at night, possibly harming the fragile seedlings. Tomato plants like warmth.

Potted tomato seedlings growing in biodegradable peat moss pots

I germinate the seeds before planting them for two reasons. First off, I’m not wasting time waiting for a plant to emerge from the dirt that isn’t coming and second, I can keep the plants that show the most plant vigor or good health, the ones that burst forth early with their strong little roots.

Germinating First

Take six paper towel sheets and stack them evenly on top of each other. Place them into a container or baking pan that will hold a little water… one with sides, in other words. Wet the paper towels thoroughly. Place your hand over the towels and pour off any excess water but still keep them very wet. Place your seeds on one-half of the wet paper towels, spaced a little, and then fold the other half of the towels over the seeds. Put in a dark place.

Begin checking on them in a couple days. Healthy seeds should take only a few days (within a week) to hatch and show their root. You can remove the ones that get a tail long enough to plant (a half inch to an inch or so, it’s up to you).

Be sure to check on your germinating seeds daily. Once they kick off they grow quickly. Additionally, make sure the towels stay wet.

Okay, my seed has a nice tail; now what?

Growing Medium

Many of us are familiar with your standard peat-pellet. It is a small, flattened disc of compressed soil that expands when placed in water and is the perfect medium from which to begin growing your plants. These are available at any garden center. They actually make peat pods specifically for tomatoes.

Tomato growing medium

After you water the discs and they’ve swollen up to their full size, take a pencil or some such instrument, make a hole about a half-inch deep in the top and place a seed (root down) into the hole. Gently pack the soil around the seed. If you have an artificial light source such a grolux bulb or an aquarium light, place it over your peat pots containing the seeds - the closer the better (to within 3 inches).

 >> Buy Peat Pods <<

When the plants are 2-4 inches tall, transplant them into a larger pot. In a few weeks, you’ll have a healthy little plant ready for your garden or greenhouse.

Tip: When introducing your indoor plants to outdoor living, do so gradually. Place the plants in semi-shade then move them more into the sun as they get used to the intensity of hot sunlight. A few days or so should work.

Ready Set Grow!

Preparing the soil a few weeks in advance of planting is wise to do. This involves making sure the planting area is weed-free and that some fresh topsoil with nutrients has been blended into the earth. A 6-inch covering raked in works nicely. This allows the tomato plants to focus their energy on growing rather than battling weak soil and weed seeds. Always use sterilized soil.

When to Set Out Your Plants

When it comes time to transplant your young tomato plants, a good rule of thumb is to not plant them outside until at least 2 weeks past the last frost of spring. This ensures a sudden cold snap won’t return to kill them and also allows time for the soil to warm up.

Tomatoes love sunshine and warm weather, so plant them in a sunny place in your garden or greenhouse.

Container Growing

Many people appreciate the convenience that container growing affords them. With this method, you have more control… or at least easier access to your plants. In containers and up off the ground, there is less chance of those insect invaders finding your plants while perusing the garden smorgasbord. Additionally, in containers, all nutrients and moisture go directly to the plant, thus eliminating competition for food and water, not to mention eliminating all that bending over while weeding and nurturing them.

Growing tomatoes in containers

The type of container you should use is up to you. Big pots, terracotta tubes, and grow-bags are just some of the options available to you. I touch on feeding your tomatoes a little further down in the article.

Tomatoes like to grow, so it is important to provide some means of supporting the plant to keep the tomatoes off the ground. If you prefer a natural material, a bamboo cane or other wood type structure works nicely. For traditionalists, tomato cages are the way to grow.


When it comes to watering tomatoes, there nearly are as many views and opinions as there are varieties of tomatoes. Here’s what I’ve learned.

A lot has to do with where you live, water availability, and what you find works best for you. While genetics account for much of the taste (some tomatoes just taste better than others), there are some techniques that come into play that may help Mother Nature enhance the flavor.

In the South, where I live, many farmers don’t water their tomatoes except for the first few weeks until the plant is established. The reasons are that, at times, it is impractical to get enough water to the plants regularly when the temperature is in the 90’s most of the summer, especially if they are in an area away from a water source. Moreover, the less you water, the deeper the roots will have to grow in an effort to find water. A strong root system generally means a healthier plant.

Moreover, studies have shown that when a tomato is deprived of water or dry-farmed, the flavor is enhanced. The science behind it suggests the water-stressed tomatoes produce more sugars, lycopene, and soluble solids thereby increasing their flavor. Quality is improved but quantity is somewhat reduced.

Around here, they don’t water again until there is fruit on the plant and then they water deeply but infrequently. Test for yourself. Set aside a few plants to water infrequently and then juxtapose them against the ones you watered more often. See if you can taste a difference.

However, if you just can’t stand to see your little friends shriveling up then go ahead and water them as you will. They are yours.

Feeding Your Tomatoes

While there is any number of fertilizers and plant foods available, food that is plant specific seems to work rather well. The food of choice for my tomato-growing friends is a product aptly named Tomato Tone. Tomato Tone works great, but do some research to see if you might like something else better.

Recommended Product: Tomato-tone

When you are transplanting your tomatoes to the garden, throw a little fertilizer in the planting hole first, but be sure and toss in a handful of topsoil on top of the fertilizer. You do this so the delicate roots don’t come into contact with the fertilizer as contact could burn the fragile roots at this stage of their growth.

This gives them a nutritious start.

Thereafter, you wait until the plant has set fruit before fertilizing again. Place the correct amount of plant fertilizer/food (according to directions) in a circle around the plant and about six inches away from the stem. Again, this is so the roots won’t get burned.

Oh, this is very important. Be sure to water your plants before you fertilize. After watering your plant, then water the fertilized soil. A well-hydrated plant ensures it won’t take in too much fertilizer all at once that can burn and damage young plants.

Two Types of Tomatoes

Determinate and indeterminate are the names given to the two types of tomatoes. Determinates are shorter, bushier, and produce their yield pretty much at the same time while indeterminates are long, vining plants and will bloom indeterminately until frost comes.

Determinate tomatoes
Indeterminate tomatoes


I want to mention that pruning can also be an important part of growing delicious and abundant tomatoes. Pruning, essentially, is removing or pinching off sickly, weak, or damaged leaves and branches. Pruning causes the plant to become bushier with new growth that the leaf removal triggers. You’ll have shorter and less spindly plants when you prune.

pruning tomatoes

The video below shows you how to prune tomato plants. It’s fun for you and healthy for them.