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The Best Way To Start Tomato Seeds Indoors – The Secrets To Starting Tomatoes From Seed!

Looking for the best way to start your tomato seeds indoors to grow incredibly healthy and strong tomato plants this year?

Starting your own tomato plants can not only be fun and rewarding, it can save you a tremendous amount of money. Tomato transplants in stores can be quite expensive, and seem to getting even pricier with each passing year.

A pack of tomato seeds can be one-quarter of the cost of just a single plant in a nursery. And if you happen to be planting heirloom or open-pollinated varieties, once you purchase your seeds, you can save even more by saving seeds from your plant each year to plant again for free!

Tomato seedlings growing indoors in grow cells.
Starting your own tomato plants from seed lets you grow all kinds of unique tomatoes. Even more, it also allows you to grow the strongest, healthiest plants around!

But beyond saving on your garden budget, growing your own tomato plants from seed opens up your world to a huge variety of unique and tasty tomatoes you simply can’t find in stores. When you purchase tomato seedlings at a nursery or garden center, you are limited to only growing the varieties they carry.

Unfortunately, stores typically only sell the most popular and common varieties – leaving incredible heirloom varieties like Cherokee Purple, Mr. Stripey, Black Krim and hundreds of more tomato types out of your garden. But when you grow from seed – the sky is the limit! See: Great Heirloom Tomatoes To Grow!

 Growing Simple – The Best Way To Start Tomato Seeds Indoors

Here’s the best part of growing your own tomato plants from seed – not only is it simple and easy, it doesn’t require all kinds of special and expensive equipment.

In fact, all you really need are good seeds, a few seed trays, great seed starting soil and a couple of ordinary LED or fluorescent shop lights – and you can grow amazing plants. The good news is that other than seeds and soil, all the other items can be used year after year for even more savings.

Nursery-grown tomato seedlings in white row pots.
Purchasing tomato transplants from garden centers can really start to add up. Even more, like the yellowing plants above, they are not always healthy and strong at the time of purchase.

With growing great tomato plants from seed in mind – here is a look at exactly what you need and how to start and grow your seeds like a pro this year!

The Best Way To Start Tomato Seeds Indoors

What You Need To Grow Great Tomato Plants From Seed

Two of the most critical things you will need to grow healthy tomato plants are larger seed starting trays and good seed starting soil.

There are a lot of options for seed starting trays, but it’s important to make sure that your growing cells are large and that they have good drainage. Look for seed trays that are bigger and hold only 6 or 12 plants. Affiliate Link: AAAmercantile Extra Deep Seed Starter Trays

Seed trays that are 2″ x 2″ are best as they allow for big root growth. Avoid using small cell seed trays that have small growing areas. They may let you start a lot of seeds, but they lead to a lot of work and can be hard on your plants.

Seed starting trays with a plastic cover on top. The Best Way To Start Tomato Seeds Indoors
Look for larger seed trays that can allow plants to develop uninterrupted until planting day.

Unfortunately anything smaller than 2″ x 2″ and you will most likely need to transplant your seedlings into bigger cells in a few weeks. Each time you have to transplant, you slow the growth of your plant. But bigger growing cells allow you to make it all the way to outdoor planting day.

The Right Soil – The Best Way To Start Tomato Seeds Indoors

Soil is everything for tomato seeds and plants! When starting any vegetable plants indoors from seed, using high-quality seed starting soil is a must.

Ordinary garden or top soil will not lead to good results. The soil is simply too dense and does not have enough nutrients for seeds to absorb and grow. Straight potting soil is not bad, but by adding add worm castings, compost and other light nutrients to it you can make it much better.

The important part is that your seed starting soil is fertile, light, and drains well. The best way to ensure success is to use a soil that is marked especially for starting seeds to help your plants germinate and grow strong roots easily and quickly. Affiliate Product Link: Espoma Organic Seed Starting Soil

Lighting For Your Seedlings

Last but not least, unless you happen to have a greenhouse with all day light, you will need to provide artificial lighting to grow great tomato transplants.

Your lights should be about one inch above the top of your seedlings to let them grow slow and strong.

Sunlight in a window or windowsill will not be enough to develop seedlings properly. It will leave you with weak, skinny plants that will not transplant well. But there is good news – providing that artificial light doesn’t have to be difficult or expensive.

One thing is for certain, you don’t need to purchase lights labeled as “grow lights.” Not only are they overly expensive, they simply aren’t needed for vegetable seedlings. In their place, you can use basic fluorescent or LED shop lights. Even better, they also happen to be inexpensive to operate.

In order to be effective, the lights need to be about an inch above the top of growing seedlings. This means that you will need to raise the lights as the seedlings grow. 

Most shop lights come with chains already attached. You can use these chains to hang from a shelving unit, or you can stack bricks or blocks and set the light over top as they grow. All you need is a way to keep the lights directly over plants by and inch or so. See: Tabletop Seed Starting Stand DIY Plans

The Best Way To Start Tomato Seeds Indoors – Step By Step Planting Instructions

Now that you have your supplies, it’s time to start your seeds! To have your tomato plants big and strong by planting day, it’s best to start tomato seeds 8 to 10 weeks before your last spring frost date. Most packets will tell you 6 weeks, but 8 to 10 weeks is better. It provides you with plants with far better roots.

The Best Way To Start Tomato Seeds and Plants Indoors
Do not grow tomato seedlings in a sunny window. It will develop long, thin plants that are extremely weak.

To begin, fill your containers and lightly moisten the seed starting soil. Leave about one-half inch at the top of each growing cell or container. Place 1 seed in half of the cells and 2 seeds each in the other half and lightly cover seeds with additional soil. It’s always better to plant more seeds than you need in order to account for a lack of germination. 

Lightly spray the soil again with water using a spray bottle after planting. Cover the containers with a clear plastic lid or plastic wrap to help retain moisture and heat. Keep the soil moist but not overly saturated. If you see condensation develop in a day or two on the plastic covering, then your moisture levels are just right. 

Tomato seedlings should germinate in around 7 to 10 days. Once the seeds start to germinate, remove the plastic cover and place your seedlings under your lights. Keep the lights on for 12 to 14 hours each day.

Remember to keep lights about one inch above the top of the seedlings. It might seem too close, but this helps to prevent plants from growing tall and leggy.     

Maintaining Seedlings – The Best Way To Start Tomato Seeds Indoors

Keep the soil in your containers moist as the seedling grow. Water carefully at the sides of plants. Try to avoid watering directly on top of young, tender seedlings as it can topple them over. Continue to raise the lights as needed to keep about a one inch gap above the top of the foliage.

Once the seedlings are a few inches tall, thin them so that you have only one plant per growing container. You can transplant the discarded extra seedlings into empty cells or add them to your compost pile. 

When it is about two weeks before you want to plant your transplants outside, it’s time to start the hardening off process. This helps to toughen up the seedlings and prepare them for outside conditions. 

Planting Tomatoes - The Best Way To Start Tomato Seeds & plants Indoors
Once the weather allows, it’s time to transplant the tomato seedlings you started indoors outside into the garden.

To harden off, set seedlings outside during the day in a protected space. Bring them back indoors at night – and during the day if weather becomes adverse. Gradually, increase the time they are outside each day.

Eventually, start leaving them outside 24/7 but continue to water them as usual. Once the weather and the soil warm up enough, it’s time plant your transplants in the garden. And, of course, get ready for that big harvest of juicy tomatoes coming soon!

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