Picture of Grow Tomatoes from Seed
I have been a tomato grower since 2008 when I grew my first tomatoes from seed.

Growing tomatoes from seed takes time and care, but ultimately it is not hard and the results are well worth it.

You will need either a grow light setup (cheap shop lights) or a south-facing window that gets plenty of sun (if you live in the southern hemisphere, you will need a north-facing window).

Use this instructable as a guide to growing your own tomatoes from seed.

UPDATE: Check out my new Web site on growing tomatoes. Grow Your Tomatoes
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Step 1: Get the seeds

Picture of Get the seeds
First, you need to get your seeds from a good source. I prefer online seed stores that accept PayPal, but this is just my personal preference. You can find tomato seeds in the garden center at places like Wal-Mart and Lowes. I buy mine from, who sells only heirloom seeds.

Research the seed company you are buying from to make sure they are reputable and that you will get good seeds from them.

I'm an heirloom grower, but you can choose to grow either heirlooms, hybrids, or some of each.

Step 2: When to plant the seeds

Tomatoes are typically sown 6 to 8 weeks before the last anticipated frost. Some say to sow them later, more like 5 weeks before the last frost, but either will work. Keep in mind that the earlier you start, the larger the plants will be when you plant them out.

To find your average last frost date, go to

I live in Middle Tennessee and start my seeds in mid- to late-February.
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Why not the paper ones?  Curious... leaching chemical nasties or...

Paper egg containers will hold water when you water plants, and get pretty nasty after a while, while the styrofoam ones are non-porous. I poke holes in the bottom of the styrofoam ones so they drain better, then water about once a day, depending on how quickly your soil dries out. Seeds need a lot of water to start, so paper egg cartons end up soggy.

catman529 (author)  iminthebathroom4 years ago
This year I used one 30-egg paper carton, but to avoid soaking the paper when watering, I painted it with hot wax which soaked into the paper and cooled to make it waterproof. When paper egg cartons get soaked with water, the paper softens and roots can grow through the paper, which can cause damage (planting the whole paper cup in a new pot does not make it decompose fast enough for root growth). Also, water soaking through the paper gives it more than twice as much surface area to allow for evaporation, which means you'd have to water a heck of a lot more often. I don't think there is enough outgassing of the plastic to make it a concern; after all, your plants will only be potted for a few weeks before going into the ground.
To not waste containers and space while experimenting with a stack of old seed packets (1990's on), as well as expectations of meager sun and heat in the NW, I used the 24-egg Styrofoam carton, placed in the oven with a CFL in place of the oven light...and it made a useful amount of germination heat, keeping the temperature in the 80's. It is also handy to write the data on the while lid and borders (and as well the lid can add reflective light, +/- foil to the oven surfaces). Then a spoon can simply make the transplantation hole in the new soil and then scoop out the hatch-lings from the egg carton to then fit the spoon-made new hole. Nicely, all 24 spaces had germination: basil varieties, pepper varieties, Korean radish and twisty peppers, various tomatoes esp heirlooms.. Of course for bigger seeds, not so useful...still stick the mango in a cup of water..attractive for the kitchen window sill...
jamesrdell1 year ago
I just dropped some seeds on the ground and wa-la sprouts in a few days
kpeoples831 year ago
this an excellent instructable! my tomato plants are growing well as you have shown in the pics at each step
kpeoples831 year ago
this an excellent instructable! my tomato plants are growing well as you have shown in the pics at each step
What about drainage? I make drain holes in these plastic cups with a soldering iron. Otherwise, the roots can rot if you accidentally water too much (which is very easy to do.)
Did you use grow lights and if you grow them inside do you need the lights on them the hole time there alive.I'm growing them inside droning winter.
Also, there's a hormone that plants have (and that we have artificially made in a lab) that stimulates root growth and production, so there's plenty of things to consider in the body chemistry and functions of plants and stuff like that.

What's up my fellow Marine (Tufflehounde).

No, do not keep the light on all the time, you can, but it's best to give plants a night, and a day, just like us humans and other living things.

It has to do with hormones. We heal better when we sleep at night, and our hormones are better rugulated.

Plants have a bunch of different hormones like humans and animals do. At night plants are also in their repair and rebuild mode like we are when we sleep.

I can get all technical with which hormones do what for us and for plants, but I won't.

basically they will have a larger growth hormone stimuli, and they with breath in alot more CO2 when the plants are having their 'Night Time'. Oohrah? Kill? Or Heal I should say. ;)))
davee52uk6 years ago
...and when you have got some tomatoes, leave one or two to get over ripe. Then cut them open and scrape out the seeds onto some tissue paper. Leave to dry and you have seeds for the next year.
I did not have to wait. I took them right dry for 30seconds and planted and it's as big the plant On step8.
catman529 (author)  davee52uk6 years ago
Yes, I should have mentioned that. Thanks for bringing it up. They don't necessarily need to be overripe, just at least fully ripe, when you might normally eat them. The preferred way of saving seeds is to scoop the seeds and gel into a container, and add some water so it doesn't dry out. Put it in an out-of-the-way area where mold can grow and the seeds can ferment. This removes the gel which is a natural germination inhibitor. When there is a good layer of mold on the surface of the seed/juice mixture, scrape it off and strain the seeds, rinse them and let them dry completely before storing them in an airtight container.
That could almost be another Instructable on its own....
catman529 (author)  katuah5 years ago
Yeah good I might just go and do that one sometime.
Please do. its my first year growing tomatoes in my back yard and i am still a rookie (green as my tomatoes) and i would love to know how to save seeds.
Also. Does anybody know what is the ideal soil moisture level for tomatoes? i made a Arduino controlled watering system that monitors soil moisture levels and adds water to keep the soil at the same level day after day. Its based off of the Garduino instructable. I'm just worried that i might be over watering or under watering.
catman529 (author)  winterfresh5 years ago
They say tomatoes need the equivalent of at least 1 inch of rain per week...not sure how that would work out with your Arduino system. Of course you don't want it to overwater either.
Thanks, I am going to add a LCD to my Arduino and a potentiometer so I can adjust the water level on the fly. Trial and error... Not the best but...
catman529 (author)  winterfresh5 years ago
Before I make an instructable on seed saving, check out my web page because I already have detailed instructions available...
hcold davee52uk6 years ago
One assumes you also choose the biggest and best tasting ones for thing. You know, artificial selection and all that.
catman529 (author)  hcold6 years ago
Yes, it's recommended to choose the best fruit from the best plant for seeds with good genes. No guarantee that the plants they produce will be as good as their parent, but at least they have the genes for it so you have better chances of better plants.
hi i was growing cherry tomato seeds, and once they germinated there were no true leaves, just seed leaves. No leaf bud either. How to make the plant grow again?
Give it more.time. Or plant more
Ronyon4 years ago
I also like the trenching.Our raised bed was filled with tomatoes plants, with vines growing willy-nilly, but not producing much on each vine.
Next season,I will bury those runners, cleaning up my grow space and hopefully boosting yield.
I am checking out your web site as well.
Tomatoes do not vine.
My tomatoes look the same as yours!
abhishek7274 years ago
Can't we use the seeds from the tomato itself? Are there any disadvantages to this particular approach? It just feels a bit weird to me to go and buy the seeds when we already have the tomato. Maybe the hybrid varieties you guys are talking about are seedless but...
I was just thinking the same thing. I don't see why not. As a child I used to let lemon and grapefruit seeds germinate and they came right from the lemon. If you want a special type of tomatoe then you kneed to buy the seeds if you have not been able to get the vegetable or fruit that you want to plant. Also I think that "bought" seeds are treated with a substance that helps them grow roots faster ..
I don't know of any seed suppliers in my area so plan to use seeds from the actual fruit itself. I usually throw seeds of fruits I've eaten into a flower pot and some do germinate however they usually just die off once the seedling has used up the seed. any idea how I can get the seeds (any) to start growing into a full plant?
Many times, especially with plants that reproduce sexually (as most do), the seeds that are retrieved from the fruits are not as good as the seeds from a supplier. The seeds from the supplier are grown specifically for harvesting the seeds to produce fruit-bearing plants. Seeds from the fruit may have a different mix of parentage from the seeds used to grow the plant.
ManyuX954 years ago
Oh man, :) I love how they look so hairy xD
CraTyr4 years ago
Will this technique also work for peppers? I know they are totally different plants, but if it worked it would make a nice healthier seedling.
I dont have any shop light but I do have some old lamps. I need to know if a compact flourescent light buld (CFL) would do.

Dr.Bill5 years ago
You Live The Tomatoe Electric !

I too am a tomatoe grower and have been for about 40 years.
I was forced into it when I was young. Boy am I glad.

I have grown tomatoes well into winter, indoors. (cherrys)
I make the best  Spaghetti Gravey, its to die for.
But you! You have all kinds of other recepies and for that I thank you.
Well Done.
Whales5 years ago
O_O Middle Tennessee? thats weird so do I, I start my tomatos in April or MAy... but they are usually from little plants, I tried seeds this year, and I did it in March(late i know) but my whole garden flopped this year, so next year I'm going with just pots.
awang85 years ago
Nice tutorial! I grow beefsteak tomatoes (which beefsteak I have no idea) which are BIG! Just onethink slice is enough to cover an entire sandwich! I buy all my vegetable seeds from Eden Seeds ( only sells organic seeds. All hybrids are determinate which means despite being a hybrid, it will still grow true to type. I made a kind of climbing frame thing out of chickenwire supported on 2 metal stakes. I use this to grow all my climbing vegetables. Other than that, I think you should mention that cardboard egg cartons are just as good (and are biodegradable) and you should actually start the seeds outside, with full sunlight so you don't need to worry about hardening them off.
catman529 (author)  awang85 years ago
Thanks for the input.

Let me say that all hybrids are not deterimate; many if not most of them are indeterminate. Look at Sungold, for example, a hybrid that supposedly produced 65ft indeterminate vines.

Also, cardboard egg cartons can be a pain to use because the roots may actually grow through the paper, but when planted in a bigger pot, the paper will not biodegrade fast enough to let the roots continue to grow underground. Thus, you would have to remove the seedlings from the cardboard trays, and tear a lot of roots in the process. Otherwise, your seedlings would get terribly root-bound and stunt the plant.

I would not start seeds outdoors without a heated greenhouse because I start them in mid-winter when temps are way too cold for tomatoes. Hardening off isn't a problem for me; it takes 1 to 2 weeks and then the plants are ready for the real world.
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