Growing Tomatoes from Seeds: A Complete Guide

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Growing tomatoes in my garden is more than just a hobby- it is part of my southern heritage.

My parents are from Kentucky and it just seems part of the culture to grow tomatoes.

There is something amazing about the taste of a fresh tomato from your own garden that is hard to explain in words.

If someone has never tasted a homegrown tomato, they have never had a tomato!

 

 

As I got more involved in gardening during my childhood,

I began growing tomatoes from seeds.

I enjoyed the process of reviewing the seed catalogs, deciding which ones to try.

It opened up a wide world of varieties to select from.

It was also a very economical way to grow a lot of plants- plenty for the family’s garden and plenty to share with friends.

For the small cost of a seed packet and a few supplies, I could harvest hundreds of dollars of fresh tomatoes.

Quite a return on my investment!

 

Growing Tomatoes from Seeds

As a resident of Northeast Ohio, I like to start my tomato seeds in mid-March so that they are ready to plant in the garden in mid to late May.

 

Planting Tomato Seeds

The process is simple. I use a seed starting kit that provides a tray, cell packs (pots). and a germinating dome. These kits are easy to find online or at your local garden center.

I recommend using a potting mix specifically made for containers (here is an example).

Don’t use soil from your garden as it is not ideal for use in containers.

 

After filling the pots with soil, I use a small watering can to moisten the soil.

Allow water to flow through the drainage holes until the soil is moist, but not water-logged.

Empty any water from the drip tray so that the pots aren’t sitting in water.

Follow the instructions on the seed packet, but generally seeds only need to be planted .25” deep.

Place 1-2 seeds in each cell pack and cover gently with soil.

Because the seeds are small, I often use a pair of tweezers to place each seed exactly where I want it.

After planting, use a household mister to add additional moisture to the soil and activate the germination process.

The mister is a gentle way to add water until the seedlings are established.

 

Germinating Tomato Seeds

Most seed starting kits come with a dome that covers the tray to retain moisture.

This creates a small greenhouse.

Keep the dome on the tray until almost all of the seeds have germinated.

Check daily to make sure that the soil is still moist and use the mister to add moisture as needed.

Another key for germination is to place the pots in an area that is warm in your home.

Some gardeners put them on top of the refrigerator to capture rising heat.

For those die-hard gardeners, a warming mat can be placed under the tray.

It provides bottom heat to get seeds to germinate quickly.

 

Light

After the seeds germinate, the key is to place the seeds in an area of your home with a lot of light. That is challenging here in Northeastern Ohio.

Over the years, I have improvised by using shop lights on chains that I can raise and lower as the plants grow.

There are now quite a lot of different “grow lights” on the market- some are simple and others are more sophisticated for the avid gardener.

When the seedlings are small, I keep the lights approximately 2″ above the tops of the leaves.

This encourages compact, sturdy growth.

I keep the lights on 6-8 hours a day. I use a timer, so I don’t have to remember to turn the lights on and off each day.

If you have a large window that receives a lot of light, you may be able to forgo a grow light.

However, tomatoes require a lot of light, and generally, most households don’t have sufficient natural light to produce healthy, stocky plants.

 

 

Watering Tomato Seedlings

Continue to use a mister to water the seedlings until they have at least one set of leaves.

At that point, the plants will need more moisture. A small watering can with a narrow spout is perfect for the job.

One of the keys to keeping the plants healthy is to not overwater.

I keep them slightly moist but allow the top of the soil to dry in between watering.

A professional tip is to try to keep the leaves dry, using the narrow spout of the watering can to concentrate the water onto the soil.

Leaf and soil diseases are less common when the leaves stay dry and the soil surface dries between watering.

 

Fertilizing

Approximately 4 weeks after germination, I begin to add a small amount of liquid fertilizer to the watering can for each watering.

I use about 1/4 of the recommended rate.

This provides essential nutrients to the plants and keeps the leaves green, but doesn’t burn the tender roots.

 

Transplanting Tomato Seedlings

If the plants become “leggy” or too large for their pot, they can be transplanted into a larger pot or cell pack.

When transplanting, plant the tomato in the soil up to the first set of leaves.

Tomatoes have the ability to form roots from the stem, so this will encourage additional root growth and eliminate the “leggy” appearance.

 

 

Acclimatization Process

Plants that were grown indoors need an acclimatization period before they can be planted outside.

This is also referred to as “hardening off.”

I take advantage of warm (60 degrees or more) days in April and early May to set the plants outside in a shady area for an hour or two.

This allows them to adjust to the increased light.

The plants will respond with compact growth that will prepare them for planting outside.

As they adjust to the outdoor environment, they can spend increasing longer amounts of time outside.

 

Planting Outside

Once the chance of frost has passed (usually mid to late May in Northeastern Ohio) it is safe to plant outside.

As mentioned earlier, tomatoes can form roots off of their stem, so I remove the lower 1-2 sets of leaves and plant the entire stem in soil up to the lower leaves.

This creates a strong, vigorous root system that will enable the plant to thrive in the heat of summer and produce an abundance of fruit.

And the tradition continues!

To learn more about growing tomatoes in your garden, click here.