How to Start Tomatoes from Seed Indoors (Complete Guide)

A complete guide and demonstration of starting tomato seeds indoors. Gardener Scott discusses containers, soil, seeds, sowing, heat, lights, and more to help show how to start tomatoes from seeds. (Video #254)
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Video: "How to Make Potting Soil & Seed Starter Mixes" - • How to Make Potting So...
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[@garynorcal4269]

Saw a great wall sign today. It said.."home is where my plants are" I think that's great because I just gave tomato 🍅 starts to my daughter-in-law.

[@DiscoCatsMeow]

Just an fyi. If you get mold growing on your seed trays- just sprinkle cinnamon on it. 😊😊😊 It really works. I forgot to ventilate my seed cabinet and my son was trying to keep the cats out so he closed the doors. Woke up to the fuzzies. A sprinkle of cinnamon and fresh air and it was gone. Make sure to bottom water and it won't return.

[@SusanRogersMakingItWork4Me]

Good to know! Thank You!💞

[@BRUtahn]

I am a working mom and can't always make it to my basement every day to check and see if the flats need watering. The 72 cell flats dry out fast. I have had better results just skipping a potting up step and starting them in larger containers. I use the ~2 inch square 6-cell packs to plant my seeds.

[@ggstorm9777]

Cut up old mini blind....best tags you can make💜

[@Outlaw653]

I’ve been buying my tomatoes and peppers plants for 3 years now. Just last night I started my first seeds. the pencil method worked great. Had my 5 yr old son and 7 year old daughter help. Had a fun time. Planted 60 seeds. They planted all of them. I’ve really been enjoying your videos and have learned a ton in just a few days.

[@nunu4654]

Yes I'm on point today just got done seed started!!! 🎉🎊Just like Mr Gardener Scott .. My 2nd year now.. and man watching him I'm up to a 3/4 year Gardener overnight... I have green thumb fever🍀🌷🌸🌹

[@LowcountryGardener]

I started my tomatoes seeds on Feb 10 and I'm planting them outside this week. Planting the tomatoes outside always makes me feel like the spring/summer garden season has officially began.

[@kimiyemlsmallgardendream8115]

Great grid system. My tomato’s are already out in the garden. 🍅🌶👍🏻❤️❤️

[@snemirovsky]

Dear Scott, Warm greetings from Buenos Aires, Argentina. I just started in gardening and came across your channel and your videos. You are incredibly educational, inspiring and motivating. I really enjoyed this particular video of yours, truly thorough indeed. Thank you very much! Kind regards, Santiago.

[@GardenerScott]

Thank you very much, Santiago.

[@TJtheHAWK]

The king of the vegetable garden the tomato 🍅 is. Awesome video as usual Scott. I'll be doing Pineapple, Beefsteak, Brandywine, Cherokee Purple, San Marzano, Early girl, Sweetie, Blueberry and Sungold tomatoes this year. Looking forward to the tomato season and watching your videos along the way!

[@GardenerScott]

Thanks! That's a nice list. Hope you have a great harvest.

[@LeverActionLarry]

It's that time of year! Exciting! Thanks GS for sharing!

[@juliepizzolato1911]

Just finished starting my tomatoes yesterday. I wound out doing 20 varieties...LOL. I also have all 3 of the sun varieties you also started, so I am excited for the season. Here we grow again in North Idaho zone 6a 💚🌻🌿

[@raphaellabooboo8372]

do you think we all need a support group for addicted gardeners? LOL...I'm glad to see I'm not the only one afflicted! We could call it GG

[@cuisined]

Hi Gardner Scott, Awesome Videos, You're my favorite tutor on here. You couid cut an "ear" in one of the corners, you'll always know which side is the right side. - Thanks for your videos!

[@laurabehenna9602]

I'll be interested to hear how "Sun Sugar" and Sunpeach" compare with the always amazing "Sungold."

[@simplifygardening]

Great planning using the calendar mate. Nice to see others advocating getting the right moisture before sowing, certainly better for the seed. Great tips and video Scott

[@GardenerScott]

Thanks, Tony!

[@dennisthegrower]

Hello Scott. Wow just started my first indoor seeds tomatoes, hot peppers and egg plants. I am in Michigan and will also start seeds in a green house soon. I hedge my bets here in Michigan. will plant same seeds indoor and then again in greenhouse, and direct sow. Weather is not good here, or predictable. Thank you for all the great content.

[@ancientgardening6920]

The peppers are growing well, and a few have their second leaves, so it's definitely time for the tomatoes. We put one seed from every packet of tomato in a paper towel in a ziplock in the window, and we're going to have a landrace! Some of the packets are ancient upon ancient, but it always surprises us. Oh, the reason carrots make so many seeds is because of their genetics has some sterility in it, so overplant a little so they do well.

[@happypappy]

Thank you Gardener Scott for your excellent instruction! There’s lots of gardening video choices out there, many of them quite good and entertaining! But yours has become my main Go-To channel, as I’m a fairly new beginning gardener, at least at a larger backyard scale (piddled with it for years, especially container gardening). Your instructions are so thorough, filled with years of experience, and covers every topic step by step, yet up to date with new (even if repeated) content. I’m in the Kansas City area, Zone 6, I believe, so a little similar too. I started out the last couple of years watching MIGardener (still do) and Next Level Gardening too, but find your videos to be the best, step by step, patient and thorough instruction for this old guy! (Other channels always seem to be in a rush!) I ordered way more seeds than I’ll ever be able to use this year, from Baker Creek (love supporting my own MO more local business) and MIGardener (the best bargain in seeds), and you have put my mind at ease about that! I’ll do what I can and have plenty for next year!!! Your video on seed catalogs early this year was also helpful. Thank you again!

[@hudson8865]

Thank you very much.

[@TheMrsMarvel]

I'm glad you mentioned you planted extras. I always have a few weak seedlings, so I plant extras. This year, I intentionally planted extras because I am experimenting with varieties. Glad I did because my sunrise sauce seemed less hardy. Now I know & still have something else to pop into its place in my garden. I planted about 15 micro tomatoes to give to friends & family, too. It feels great to have some to share. Tomatoes starting is exciting because there is SO MUCH POTENTIAL in those tiny seeds!

[@j.b.6855]

Nice video Gardner Scott. I made the mistake last year of starting tomatoes and a lot of other seeds way to early for 5b south of Chicago. They got way to big and since my seed starting room is in the basement it was a chore carrying up extra trays of plants up the stairs to harden off. I dont plan on putting them out until after Mothers day to make sure its warm enough. I started them about 10 days ago and they all came up. I am waiting for the second set of leaves before potting them up and planting as much stem as I can.

[@He4vyD]

I hear you, buddy. I started my tomatoes end of february, and most of them are now around 1 meter tall. And my last frost day is 15 May. I put them in a colder room of my house today to slow their growth a bit.

[@alligator_pie]

Here in zone 3b it’s not just about the last frost, but it’s the earth temperature. Tomatoes don’t like cold feet! Takes a long time for 3 ft of frost to get out of the ground. I’m trying raised beds this year.

[@ancientgardening6920]

Oh, the corner spot needs to be open with no plastic cell, cut it out of the tray and the water flows directly to the bottom a lot faster. Also remember to pile up dirt under the trays so each plant has more dirt to grow into.

[@linsaficken9746]

Thank you for sharing your systems and using other things for sowing seeds indoors.

[@stephenmoberg8807]

I’m planting mine tomorrow 3/21/21

[@melissakingery4393]

Scott I kinda lost track of you but found you again and was reminded how awesome a speaker you are!! Last year we were late, we are In Austin Texas. We are way better prepared than we were last year. I have lots of tomatoes by seed.Some have kinda withered and I had problems but had a lot turn out ok

[@melissakingery4393]

I'm also growing vertically Zucchini, straight neck squash, and Patty Pan squash

[@Pigearvet]

Good form on planting.. I got lazy this year and am hoping for the best in my solo cups lol. Good tips.

[@Angie-ci1lp]

Again! You’re a great teacher 👏🏽👏🏽👏🏽👏🏽 Thank you🥦🥬🥒🌶🌶🌶

[@carleatwell551]

A well produced video thoroughly enjoyed it all the best from caerphilly south Wales uk

[@OuttaDisWorldGamer]

Hi there very grate information thank you !,, ps don’t understand those who don’t like this video wow ! What is wrong what do you seeing and herring here if you know better why you watching this or other programs in this topics address to growing your own garden !, thank you Scott great information and I’m a gardener for pass 40 years thx again Ewa

[@yvencia1150]

Great video and thank you for sharing 🍅🍅

[@nadiamelnycky5669]

Hi Scott, thank you for wonderful video. Can you tell me when should I remove heating mat. My tomatoes all sprouted, they are in the warm place. Nadia

[@GardenerScott]

You can remove the mat after they sprout.

[@robinham2796]

You are so good Scott! What do you think about soil blocks?

[@GardenerScott]

Soil blocks can be good. but I start most of my plants in cell trays. Here's my video on soil blocks: kzbin.info/www/bejne/qJSVk4CXadp7odU

[@jennifernicholson4540]

This is the first year i am using peat pellets and i have all of my seedlings coming up, I am wondering when i should transplant them into larger containers? I have my lights going and your soil recipe ready to go. Please let me know when is the best time to transplant. Thank you so much for all of your videos. I have learned so much and am loving every minute of gardening! PS your potato video is amazing!

[@GardenerScott]

When the seedlings have their second or third set of trues leaves they should be transplanted. Thanks.

[@craigkurker6242]

Hi Scott what is your opinion on cutting the tips off of seeds to give a chance for the water to get in there in the more stir to get a quicker growth. Like squash seeds for pumpkin seeds larger seeds that have that little tip on the end.?

[@GardenerScott]

Some hard seeds need that scarification, but I haven't needed it with soft seeds like squash and pumpkins.

[@maryannesherbrook5765]

Do you use special grow lights or just any light to produce heat? Your videos are so informative and I enjoy watching them. We don’t have a very long growing season here in Wyoming so I’ve started most of my seeds already.

[@GardenerScott]

My lights are basic shop lights (I have a few videos that show that). My grow area ranges from 64-68 degrees and that's enough that I don't need extra heat, other than mats to help germination.

[@ejfishes7610]

Thank you for such a detailed video! Do you have a link for the light directly behind you in the video ?

[@GardenerScott]

There are two different ones. Here they are: amzn.to/3s6f5Cb amzn.to/3cWaETQ

[@theeyesehaveit]

After all are planted and you spray the seeds with water…..do you spray them again with water as they continue to germinate - not yet sprouted?

[@GardenerScott]

Covering them with the humidity dome is usually enough to keep the soil moist until they germinate. If it looks like the soil is beginning to dry, another spray is okay and then covering again.

[@davidmumaugh4074]

I'm new to this, so maybe a little slow on the uptake. Please clarify this for me. You mention the seed packet says to start 6-8 weeks from first frost. Six weeks from today is 5/1 and 8 weeks would be 5/15. Yet you say you won't put your plants into the garden until about 2 weeks after that around 6/1. Can you give me some guidance? I am also in Colorado 5B with a 90% last frost date of 5/24 and didn't plan to start on sowing until 3/29. Thanks very much in advance. I watch your videos all the time

[@apiecemaker1163]

He mentioned at the beginning of the video that he gives himself a two week buffer to not be surprised by later frosts in his area. Just a safety measure he uses so as not to have his tomatoes hit with a later frost. Hope that helps. Good luck and welcome to the community.

[@TheMrsMarvel]

I too fully believe in the buffer for the dates. The Last Frost Date is the LIKELIHOOD of a frost for the area based on historical data. In every place I've gardened, we've always gotten a slight cool snap after the projected last frost lol

[@apiecemaker1163]

@@TheMrsMarvel yes us too. We call it blackberry winter because generally it happens when they are in full bloom. Have a great weekend. Happy planting.

[@GardenerScott]

My normal buffer gives me flexibility, but I started a little early so I could get the video released so other gardeners can get started on time, hoping few would catch the discrepancy of the release date and my calendar. And so I can put plants in the ground early under hoops (that video is coming later). You're right in your date analysis. Even with the buffer, my plants are early, but yours will be on time. Thanks.

[@crissyprager2100]

Thank you for the step by step instruction. ? For you, I’ve started my tomato seeds yet they are looking limp and the stems are drying up. I think I’ve over watered. Will they recover if I re-pot and remove some of the wet soil from the root area? Thanks!

[@GardenerScott]

They can recover from over watering, but if the young stems are damaged they may not. Try letting the soil drain and dry a bit. I wouldn't repot unless they have their first set of true leaves.

[@crissyprager2100]

@@GardenerScott thank you! Yes they have a couple sets of true leaves. I did an experiment of two - re-potted and boy the soil was too wet. Replaced with fresh seed starting mix and did not water as the root ball was soaked.

[@heidiclark6612]

It certainly is getting close for me. I have trouble with the humidity domes like the one you are using. Once humidity collects on the dome it runs down the side and leaks out, making puddles of water on my heat mat. I am looking for a solution for this.

[@GardenerScott]

Heidi, I try to raise the dome and allow the condensation to drip into the cells as often as I can so that big drops don't build up. But I do have to wipe up the mats when puddles form.

[@wormulous]

I'm truly just waiting for my plants to decide to warm up and start getting true leaves. I started early on heat maps but I'm not sure why they arent growing. It could be heat at this point or even a lack of nutrients. I'll be adding some really diluted fertilizer just to see how that works or I am going to need to pot them up and move them into the warmer places of the house with grow lights. Will seedlings stop growing for a while after germination if they are cold? They seem very healthy so like I said I'm just curious if there is something wrong or I'm just being too impatient. No true leaves yet and I started about 3 weeks ago.

[@GardenerScott]

Cold air can slow the growth of plants. You may notice the plants perk up if you can provide supplemental heat.

[@wormulous]

@@GardenerScott thank you! Yea they are struggling where they are right now. I have some ideas for relocation, but it's going to take some maneuvering since they are currently in the garage and the entire house isn't open to be taken over for seed starting.... I know it's silly, but not everyone is as excited as I am here 😂🤣.

[@corabriones8259]

Gardner Scott , Do you use cardboard in your raised beds ? If so , how is it layered among the soils ? Thank You

[@GardenerScott]

I don't because my tall beds kill any grass or weeds underneath. For shallow beds, to kill plants underneath, a double layer of cardboard at the bottom can work.

[@living_in_wellness_gardening]

This is going to be my first year where I attempt to germinate seeds indoors... I don't want to spend money on a heat mat... As an alternative, I'm thinking of using the wet paper towel method in Ziplock (placed on my register for heat) to sprout the tomato seedlings. Once they've sprouted I'll immediately transplant them into seed starting mix and put them under the grow light... I know this is unconventional, and that's what intrigues me to try it!... Do you have any tips or suggestions for what I'm about to do? Or foresee and possible issues I need to look out for? Thanks in advance for your feedback! :)

[@GardenerScott]

It is not as unconventional as you think. Putting the seeds on top of a refrigerator or other warm spot can aid germination. Check the paper towel at least once a day so you can move the germinated seeds into potting soil before the roots grow into the paper.

[@living_in_wellness_gardening]

@@GardenerScott Thank you 👍

[@feliciacarter1962]

Hello GS. I ordered the heating mat, but I didn’t see a link for the light. I have everything else.

[@GardenerScott]

Thanks, Felicia. Here are the light links: amzn.to/3s6f5Cb amzn.to/3cWaETQ

[@faramarzmokri9136]

What are your most favorite tomatoes that have most flavor? Thank you.

[@GardenerScott]

I really like Black Krim. Here's my video of other favorites: kzbin.info/www/bejne/hp7ap6pupdd4qqM

[@InnocentCorgiPuppy-su4dq]

👍

[@aleysechapin3440]

What do you do with the extra seeds that don't get planted? Can they be saved for the next year?

[@GardenerScott]

Yes, most seeds can be saved beyond one year. I try to use open packets from previous years when I start seeds.

[@elisataylor556]

What temperature should the actual growing room be? My tomato seeds thought they wanted to come up then they didn't and I wonder if it's because my bathroom isn't heated and stays around 50 degrees. Should I put a heater in there? I used the heating pad to germinate. It's like a few came up and then 2 days later they were gone. I'm just not good at small seeds.

[@GardenerScott]

A room with around 65-70 degrees is ideal. I think 50 would be too cool.

[@smallsproutsgarden2813]

Hi, Scott! I currently have tomatoes in large size peat pellets. Sowed on 3/1. I noticed today that I have root growth outside the pellets. Should I pot up? If so, should I use seed starting mix or standard potting soil? Thanks so much!

[@GardenerScott]

Yes, once the roots grow outside the pellet it's a good sign to pot up to a potting soil.

[@rabbad7228]

I planted tomatoes and i every day i sprinkle it with water mix with alcohol but insects dsmage the leaves and made it curly and wrinkle leaves

[@GardenerScott]

The plants may not like the alcohol and it can damage the leaves too.

[@rabbad7228]

@@GardenerScott but i mixed with water to reduce and eases effect alcohol and i tried it with another plants this choice better than pesticides

[@rabbad7228]

@You Tube thanks i will stop this method

[@johnjude2685]

Knats or to much moisture has killed my first try at growing my own plants from seeds. Trying to restart and stay dryer

[@TheMrsMarvel]

We have all been there, @John Jude. That is exactly the reason I had to water from the bottom of the tray & set an alarm so I don't forget to drain any excess water.

[@Farmynator]

I had the same issue, until I decided to grow the paper towel method. Try it!

[@letiziacastiglione2492]

Just a heads up that the metric measurement of the depth you have on the video is wrong. It should be 0.6cm instead of 6cm. 😊

[@GardenerScott]

If you look closely you will see a period in front of the 6.

[@raphaellabooboo8372]

Hey Gardener Scott I'm very upset because I just noticed that deer or something nibble the tops of my emerging iris and I can't find out anywhere whether this has already ruined them and if they can still flower..help!!

[@GardenerScott]

That is very unusual. Deer don't tend to like irises so I would look for other signs of what animal is the likely culprit. You might be able to put netting or buckets over them when you're not around. They probably aren't ruined and they should flower if you can protect them.

[@raphaellabooboo8372]

hmm. I just assumed it was deer since I saw droppings near there. I just put fresh garlic and cayenne pepper around them for now and I'll see what gives. Do you think I still have a chance that they will flower? I put some plastic cups on some of them with air holes in them to try and save them. I saw another dropping near by that was definitely NOT deer poop...looked more like a dog but I know that's not it. These iris are the dark almost black purple ones..I got a long time ago, don't remember the name but they are so beautiful.

[@raphaellabooboo8372]

oh, I wanted to tell you that I finally watched that documentary "The Big little Farm". OMG what an awesome film..but I was stressing thru the whole thing! ha ha ..they had a lot of stamina for sure! I never saw so many snails in my life ..they should have collected them and sold them to a French restaurant...I love snails ..for eating..not destroying my garden!

[@lesliescully3544]

Would vermiculite work instead of perlite?

[@GardenerScott]

Yes it will.

[@lesliescully3544]

Gardener Scott thank you

[@youguanhen9389]

My tomato would stop growing and start to dry up when reach bout 3inches. Very sad.

[@InnocentCorgiPuppy-su4dq]

👍

[@judyh1296]

My tomato seedlings are turning yellow. Why?

[@GardenerScott]

Could be many things, but it is most likely over or under watering.

[@shidelsresthomestead6921]

Quarter inch is 6 mm, not 6 cm.

[@GardenerScott]

If you look closely, the screen says ".6cm". I agree 6mm would have been easier to read.

[@LisetteWijtmans]

1 quarter inch isn't 6 cm. It's 0 6 cm

[@GardenerScott]

If you look closer in the video the screen says ".6 cm". I guess it's a little difficult to see.

[@user-nh3cr2kg4r]

6cm is not quarter inch 👍😀🤣😂😂

[@InnocentCorgiPuppy-su4dq]

👍