How to Grow Tomatoes From Seeds [9 Step Guide]

Growing tomatoes from seed
Growing tomatoes from seed

Picking up tomato seeds and plugging them into your garden soil seems pretty convenient. This might make you wonder – what are the advantages of growing tomatoes from seed? And this seems fair, doesn’t it? Why would there be a need to start your own seeds – when you can just pop in seeds from the local nursery?

You get variety! In many nurseries, there are various kinds of tomatoes. When you’re growing tomatoes from seeds, you have the exclusive option of choosing from hundreds of heirlooms. If you want, you can also choose from open-pollinated and hybrid varieties that are available through catalogs.

And besides, growing tomatoes from seeds lets you save money. If you have a large garden, you can save a lot!

Different Kinds of Tomato Seeds

When you’re going through your favorite tomato seed catalog, you’re going to notice descriptions like “open-pollinated,” “hybrid”  and “heirloom.” Understanding what each seed can bring to your garden will help you pick the appropriate tomato types for your garden.

But what are those different types?


An heirloom is a special kind of tomato that is open-pollinated. It has passed through various generations to become what we call today an heirloom tomato. The most prominent reason people grow an heirloom tomato is their flavor. It gives the fruit mouthwatering flavors that can’t be matched by different kinds of tomatoes.

However, you’ll find a lot of diversity in heirloom tomatoes, too. The fruits can come in all kinds of sizes, colors and shapes. Some popular heirloom tomatoes are:

  • Brandywine
  • Cherokee Purple
  • Big Rainbow
  • Pineapple


An open-pollinated is a kind of seed that has been pollinated by insects, gardeners or even the wind. If the seed is saved, the seeds can be true. If a person is growing various varieties of open-pollinated squash or cucumber, there’s a high chance that they will cross-pollinate.

But if you’re growing just one variety, it’s safe to save an open-pollinated seed. Remember, all heirloom seeds can be open-pollinated, but every open-pollinated seed is an heirloom. Some examples of open-pollinated tomatoes are:

  • Glacier
  • Dwarf Caitydid
  • Dwarf Sweet Due


Hybrid seeds are created by controlled pollination. The pollen of two different breeds is selected by the farmer, and then pollination is allowed to occur. In many seed catalogs, you’ll see them under the F1 category. Usually, the F1 category can’t be saved because they aren’t “true to type.”

But you’ll find it amazing that people still grow hybrids! There are certain traits that hybrids can offer to you, too. Hybrids can at times give you better yields, they can resist diseases better, you can harvest them earlier, they can be vigorous and the ripening can also be uniform.  A very popular kind of hybrid seed is Sun Gold. This hybrid seed can give you cherry-sized tomatoes.

You may like below gardening articles to start your own garden:

Which One Do I Grow?

How to Grow Tomatoes From Seeds

Now that we’ve given you a basic background of tomato seeds, let’s decide which one you should grow. When you open a seed catalog, you’re going to find hundreds of different kinds of varieties of tomato seeds. But when you have such a huge variety of tomato seeds to choose from – which one do you select?

To make this decision – consider the following three questions:

1. What Kind of Space Do You Have?

The growing habits of a tomato can be broken down into two definitive categories. Which are:


These varieties are optimal if you have a small space or a container garden. When you’re growing a determinate variety, the fruit can be three to four feet tall. While they grow in size, they also mature. These kinds of tomatoes can be perfect for canning or for tomato sauce. Unlike the indeterminate variety, they can also mature a lot quicker.


Often called vining tomatoes, these are the big guys. These kinds can grow 7 to 8 feet tall. They’ll continue to grow until the first frost date kicks in. There might be a need for you to support them. You can get a container and grow them in it, but we suggest you find a large pot and support them with a trellis or a stake.

2. How Long Is Your Growing Season?

Flipping through the catalogs, you’ll notice that tomatoes are categorized by the time they can take to mature. This can be early, mid or late-season. You can also address this as days to maturity. The days to maturity can tell you how many days a seed will take to give you fruit, starting from the time it was transplanted into your garden.

If you have a short-growing season or a garden by the coast, try growing tomatoes that mature fast. You can choose from different kinds of tomatoes like:

  • Sun Gold (57 days)
  • Northern Lights (55 days)
  • Moskovich (60 days)

If you want to figure out the length of the growing season in your area, try checking this website.

3. How Do You Intend to Use the Tomato?

There are many different kinds of tomatoes that an aspiring gardener can grow. These can be:

  • Paste
  • Cherry
  • Slicing
  • Grape
  • Cocktail

If you’re trying to decide how you want to grow your tomatoes, try to ask yourself, what am I going to use them for? Some people like to enjoy their tomatoes fresh from the garden, and some people like to use them for sauces. That is why, planting a mixture of different kinds of tomatoes can be a good strategy.

Include some tomatoes that you can use for sauces, some beefy heirlooms that can be used for slicing, and some sweet grape or cherry varieties.

Growing Tomatoes From Seeds: A Step-By-Step Guide

Now, we will see how to grow tomatoes from seeds through a step by step guide.

Step-1: Sowing Seeds at the Appropriate Time

Growing tomatoes can take six to eight weeks. This process will include sowing and transplanting. If you start your seeds indoors, you might get overgrown or leggy seedlings. The goal should be to plant the seedlings a week after the last spring frost date. You can find out your last frost date by counting backward by six weeks.

That’s when you should be sowing seeds indoors.

Step-2: Your Containers Should Be Clean!

You have to be able to use your growing space efficiently. Try sowing your seeds in a plastic cell pack. You can reuse them and you can cram hundreds of plants under grow-lights. If you want, you can also try using a recycled yogurt container, a plastic pot or a milk carton.

Step-3: The Seed Starting Mix Should Be High-Quality

When your seeds are growing, they should have a mix that is excellent. Try using a lightweight or a well-draining mix. Before you fill the mix into a pot or in your choice of container, moisten it evenly. Make sure there is no uneven wetting.

Step-4: The Depth You Plant Seeds At

Tomato seeds can be very small, so if you plant them too deeply, there’s a chance you might not see them again. Sow the seeds about one-quarter inch deep and cover them lightly with a moistened mix. Label all kinds with a wooden or plastic tag and make sure the name is written with a permanent marker! If you don’t label them, you’ll forget.

Step-5: Provide Ample Amount of Light

This is an important step for Growing tomatoes from seed. Healthy and sturdy seedlings need a lot of light. If you provide too little light, this can cause legginess. Because of this, the seedlings might stretch, and they might flop over and fall. The perfect place to start tomato seedlings is under a grow light. Under a grow light, you control the amount of light your plant gets.

Some people use inexpensive grow lights. These lights are four-feet high and can be hung with chains on anything around your house. As the plants start to grow, the lights can then be moved upwards, so they are always only a few inches away from the foliage of the plants. You should let the lights stay on for at least 16 hours a day. Some lights also come with a timer, which can automatically turn them off after the time requirement has been met.

If you don’t have a light, you can also use a sunny window. But in the late winters, you might see some low-light conditions, so expect stretching. If you intend to make the starting of seeds a yearly event, we would advise that you invest in a grow light.

Step-6: Maintaining Moisture

Can we grow tomatoes from seeds
Tomatoes in a basket

You can kill delicate seedlings by overwatering them, that is why keeping an eye out for moisture is crucial. The soil can be moist, but it should not be wet. Once you’ve sown the seeds, use a plastic wrap sheet or a plastic dome and place it on top of the containers and the trays so that you can maintain the levels of moisture.

Once germination starts to occur, remove the covers so your plants can get air.

Step-7: Provide a Lot of Air

As indicated in the previous step, air circulation is vital when you’re growing healthy plants. If you’re planting your crops in a closed area like a basement – you can’t expect a lot of air circulation. To combat this issue, we recommend getting a fan that can oscillate and provide your plants with air.

Moving air can also toughen up the foliage of the seedlings and the stems of the plant.

Step-8: Feeding the Seedlings

There are also many potting mixes that can give your plants fertilizer slowly, and this process can happen over several weeks. To supplement this process of fertilization, you can add organic water to the mix. Remember to apply casually every 12 or 14 days.

The potting bags and fertilizers will have labels, so make sure you read them carefully.

Step-9: Harden the Tomato Seedlings

This is the last step if you’re growing tomatoes from seed. Once you reach the frost date of spring, it’s time you start hardening your tomato seedlings. Hardening is the process when indoor-seedlings are accumulated to the garden outside.

You can expect this process to take 5 to 7 days. You can start by putting the seedlings outside in the shade for a few hours. In the night, bring them back inside. Continue this process and introduce the seedlings to more sunlight with each passing day. They’ll be ready to be transplanted into your garden or the containers within a week.

Your tomatoes will need a soil temperature of at least 60F or higher to grow. If your soil isn’t this warm, hold off the transplanting process until it is. There are soil thermometers that can help you check the temperature of your soil. Remember: this isn’t the air temperature!

If you’re ready to transplant your tomatoes, water them generously before their transition into the soil. Dig a hole that is a bit larger than the spot you’re transplanting from. Add some compost or worm castings to the soil too. This will make it more organic for the tomatoes.

These are the steps for Growing tomatoes from seed and you can easy grow tomatoes from seeds.


If you want the best setup possible for growing tomatoes from seed – a greenhouse can be the ideal choice. A greenhouse gives you the space to start planting your favorite summer vegetables. If you’re lucky enough to own a greenhouse – growing plants in a greenhouse is definitely the best decision you can make.

By using a greenhouse, you can provide your plants with your choice of heat, humidity and light.

You can check a few vegetable gardening blogs:

The Bottom Line

Have you grown tomatoes from seeds before? If you haven’t – now is the time to start! Growing them your own way gives you a lot of benefits. You get to save money, you have an exciting new hobby and you can always stay sure that the crop you’re getting has no artificial additives.

Growing tomatoes from seeds also gives you a wide variety of options to choose from. If you simply buy the tomatoes you use from the market – you’re limited to the variety they’re selling. While you can use every tomato for every tomato-related task, a customized one just hits a different way. It makes your job easier and your food healthier!