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Germinating Tomato Seeds Indoors

Germinated Tomato Seeds

Look! Baby tomato seedlings!

Look! Baby tomato seedlings!

Germinating Tomato Seeds Indoors

I always look forward to Spring, everything is growing and the garden is ready for plowing, tilling in order to prepare it for delicious vegetables that I can grow myself and enjoy fresh from the vine, stalk or earth. However, the thing that I’m most excited about in Spring is the fact that I can get an early start on my tomato plants and have a crop sooner by having seedlings ready to transplant into the soil.

Why Germinate Tomato Seeds Indoors?

One big reason I, and anyone else who germinates their seeds indoors, do this is to give my tomato plants a head start. Tomato plants can be germinated, grown indoors and kept happy in their own little pots until your garden is ready to receive them, allowing you to have plants that mature and set fruit earlier in the growing season, ergo juicy tomatoes sooner!

The second reason of course would be related to frost. Tomatoes love warm temperatures and nights that aren’t too cool, preferably above 55˚F. Most regions can still experience cold snaps and frost even when the daytime temperature is perfect for tomato plants. For that reason, most gardeners would have to wait too long until all danger of frost had passed before planting their seeds if they intended to grow tomatoes from seed. Of course, if your growing season isn’t particularly long or suited to plants like tomatoes, then you’re out of luck unless you give your plants a head start or you purchase plants from a greenhouse.

Makeshift Miniature Greenhouse For Tomato Seeds

Rotisserie chicken containers make great greenhouses for starting seeds.

Rotisserie chicken containers make great greenhouses for starting seeds.

What Do I Need To Germinate Tomato Seeds Indoors?

Light, water and some seed starter growth medium or potting soil is basically all you need. I collected and used old rotisserie chicken boxes with transparent lids as miniature greenhouses. These work great at sealing moisture and warmth in, encouraging the seeds to sprout and grow quickly.

I simply took the clean rotisserie boxes and added some moist, not soggy, potting mix, spread a few seeds over the soil and covered them with a fine layer of potting mix, being careful to not bury them too deeply. The general rule of thumb is to plant your seeds as deep as their widest point, and tomato seeds are very small. Gently mist this top layer and place the seeds somewhere warm, such as a sunny windowsill or somewhere that the seeds can receive sunlight. Another great thing about rotisserie boxes is that the bottoms are black and sunlight striking them will warm the soil inside, encouraging germination.

What Do I Do After The Seeds Have Sprouted?

Within a week you will begin to see shoots and baby leaves sprouting from the soil, if your seeds were viable or “good.” After most of your seeds have sprouted, it’s a good idea to pull out any seedlings that are growing too close to one another. If you planted too many, simple pluck out the weaker seedlings and leave the largest and healthiest looking ones to continue growing. There’s no hard and fast rule for how many can be growing within a certain amount of space. Simply use good judgment based on the size of your seedlings and go from there.

Transplanting Tomato Seedlings

Tomato seedlings transplanted into buckets

Tomato seedlings transplanted into buckets

When Do I Transplant My Tomato Seedlings?

When your seeds first sprouted, they had a pair of very simple leaves, called cotyledons or “baby leaves.” What you want to see is the true leaves characteristic of tomato plants. These will look like tomato leaves obviously, but they’ll just be small for the seedlings’ size. When these appear, you can transplant them into their own pots that are about 4” inches in size. This will leave them plenty of room to grow on their own for the short term until the danger of frost has passed.

When you transplant the seedlings, plant them in their new containers to a depth that covers the cotyledons, leaving the true leaves above the soil. Tomato plants root very easily when their stems and or vines come into contact with soil. The seedlings will grow roots along their main stem up to the point that the cotyledons meet the soil, giving the seedlings an extra leg up and encouraging growth.

When you have placed the seedlings in their larger pots, water them gently to settle the soil around their roots. You can begin watering them with a diluted solution of balanced fertilizer, mixing it at half the recommended rate of the label. This will provide them with enough nutrients while avoiding burning the roots and killing the plants.

Growing Tomatoes In Buckets

Tomato plants growing in buckets after transplanting

Tomato plants growing in buckets after transplanting

When To Transplant Tomato Seedlings Into The Garden?

Before you begin transplanting the seedlings into the soil outside, the plants must be acclimatized to the outside temperature and sunlight. If they were set out immediately, they could suffer shock and wither and die. Instead, we must set them out in the sun for a few hours a day, and gradually increase the amount of time they’re outside until they experience full sun all day. Make sure to keep them

When the danger of frost has completely passed in your region, you can begin transplanting the hopefully larger seedlings into the soil. The process is basically the same as when they were transplanted into their own pots. Simply dig a hole in the soil that will allow you to plant the seedling at a depth that covers more than the current base of the plant. You can strip off some of the lowest branches and leaves and they will sprout new roots as well as long as they’re in contact with the soil.

This helps in many ways by improving the plants access to nutrients and moisture in the soil. Simply water them well to settle the soil around the roots of the plants.

Gardening As Usual!

Simply tend to your tomato plants as usual, staking them up or caging them as they grow. In no time, you’ll have bushels of juicy homegrown tomatoes for slicing, making salsas and sauces and sandwiches. And these will be a great deal better tasting and more nutritious than the commercial tomatoes most grocery stores and super markets carry. The reason being that those commercial tomatoes are picked green, not even red! They’re artificially ripened in transit. This leaves them with poor flavor and us with something to desire for. Of course, growing your own is very rewarding and tasty!


Jeremiah Simpkins (author) from Pulaski, VA on March 09, 2012:

Thanks am9905d! I give all credit with regards to the chicken boxes to CJ Andrews. I never would have thought of it myself. :)

am9905d from Greece on March 09, 2012:

We always germinate our tomatoes seeds indoor, last year I tried to build a small outdoors diy greenhouse but it didn't last long.

I loved the tip about the chicken boxes.

Well done

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