Starting tomatoes indoors

[lee53011]

I was wondering when everyone starts their tomato seeds. Four, six, eight weeks before last frost? What size container do you start them in and do you move up a size later, etc? Do you fertilize?

[GoDawgs]

I usually figure about when I want to plant them out (weather permitting) and then sow seeds in small cups 4-5 weeks prior to the planting date. That will give me sturdy 6" plants. The seeds are started in small individual pots the same as these micros are starting in and are set under adjustable lights. I like these little pots because they're 3.25" deep.



If the weather turns bad and if it looks like they might need to be held back and would get leggy, I'll sometimes transplant them to 24 oz cottage cheese containers. They get plain old Miracle grow solution when the first true leaves appear.

[edweather]

I start very early, maybe 10 weeks before last frost. I like to get a big jump on the best part of the season here, before the heat, humidity, disease, and bug fight begins. I start in small pots similar to above, and usually pot up twice. Then the tomato two-step begins when the weather is nice. I also use a weak MG when plants are small, and increase potency as they grow. I'll be starting seeds Jan. 2

[bower]

Here in the North with a short season, I aim to give mine 6-8 weeks indoors before they go into the greenhouse, and will usually start them sometime in March. I start my seeds grouped in cells on the heat mat and move them to individual 9-cells when they shuck their seed (72 per 1020 tray). Some people wait until they have true leaves to transplant but I have never done that and it's never been a problem, they don't even wilt. I use a tiny pinch of bonemeal in the 9 cells and a bigger pinch gets mixed into the lower 3/4 of the beer cups which I pot up into when they have at least 1 set of true leaves. I used to use 4 inch pots but the beer cups have about the same volume of soil with a deeper profile and a smaller footprint on my windowledge setup, so I can cram in a few more.
If the forecast is good I'll start planting at 6 weeks, but more often it's 7 or 8 because our springs are cold and late. By 8 weeks they are starting to need to go out - run out of root space in the beer cup and running out of head space in the crowded indoor grow space. So it wouldn't help me to start any earlier - I don't have space to pot up and keep inside. Most tomatoes will have seven true leaves in six weeks, a lot of them will start to make buds at that point as well.

[lee53011]

Has anyone used the 3" Jiffy Pots? Pro's, con's? Would they be good for 6 weeks? Or would red solo cups with a hole in the bottom be better? I also have 3" square pots that are about 3 1/2" tall.

[Rockoe10]

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Welp, I started some of mine before winter started here in PA .

I've already got done flowers on them and I'll end up taking cuttings come spring time to plant outside.

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[Cole_Robbie]

About the solo cup question above, they work ok, but they will get top heavy and fall over easily when the plant gets bigger. I usually would broadcast sow into vermiculite or a very loose mix, then transplant to 48 cell trays, then to 4" square pots. It is a little better for roots to be transplanted than to be started in a big container, makes them fill the space better.

As for timing, for me that is a call on the weather, which has been unpredictable in recent years. It goes from 25 to 75 in about a week or two. The more years go by, the later I have started seeds. It is a little easier for container plants to be grown early, but for plants in the ground, they won't grow until the soil warms.

[brownrexx]

I start mine about 6 weeks before my last frost and I start them in sterile soiless mix in little cell pots. When they get big enough I transplant them into 4" square pots.

20200315_155518 by Brownrexx, on Flickr

20190422_185310 by Brownrexx, on Flickr

DSC01298 by Brownrexx, on Flickr

[lee53011]

[mention]brownrexx[/mention] do you fertilize at any point before planting outside?

[bobrarian]

[mention]lee53011[/mention] - I'm still figuring this out myself, but what I did this year seemed to work for me.

I started seeds in paper cups - about 10 oz. After they got to about 4 inches tall, I potted them up to 4" pots. Then eventually potted them up to 6" (1 quart to a half gallon?) nursery pots. They were probably a good 14 to 18 inches tall when they finally made it into the containers outside.

Regarding timing, I'm in a zone 10a, where the last frost date is supposedly between Feb 11-20. But to me, that's too early, because the nights are still too cool - low 40s and sometimes lower than that. This year, I started the seeds 2/17, and transplanted on 4/11 and 4/18. Thankfully, we had a mild spring and summer, with the real heat not arriving until early August. This time, I plan to start seeds 2 weeks earlier, aiming to transplant mid to late March.

You also asked about 3" Jiffy pots. While I haven't used them, my initial thought is that they may be a bit small to keep seedlings in there for 6 weeks, but I could be wrong.

[mention]Rockoe10[/mention] - those indoor tomatoes look really nice!

Bobby

[Amateurinawe]

[mention]Rockoe10[/mention] loving the idea of taking cuttings for spring planting outside.

[brownrexx]

@brownrexx do you fertilize at any point before planting outside?

Yes, after my seedlings develop their first true leaves in the small cell packs, I fertilize with a dilute liquid fertilizer, maybe half strength, once a week. The soiless starting mix has no ferts in it.

When I transplant into the square pots I use an organic potting mix with ferts so I quit using the liquid fert when they get into those pots.

[habitat-gardener]

In late summer I was talking with one of my fellow community gardeners about the hybrids she got from a friend. She loved the tomatoes and didn't think she would ever be able to get them again (not commercially released), so I suggested taking cuttings. And then I thought, I never tried taking cuttings from healthy plants in the fall, so I tried a bunch, too. I put the cuttings in water, then planted the ones that still looked good into 1-gallon pots. (Quite a few turned to slimy mush before I got around to potting them up, despite water changes every few days.)

So I have about 10 gallon pots under the eaves. A couple of them are trying to flower and make fruit! We've had several nights in the 30s, but days are 50s. I haven't even kept tabs on which varieties survived so far; I will have to check labels before I start new seeds!

[brownrexx]

[mention]habitat-gardener[/mention] I had to take cuttings for the first time last Spring and some turned mushy. Someone on the forum told me to root them in potting soil and that worked perfectly. Just keep the soil really moist.

[Gardadore]

When I transfer baby seedlings to Solo cups or any larger container I mix in a tsp or 2 of worm castings to the soil and the plants grow very happily with that. Like the idea of adding some bonemeal as well and will add that this year. When I transplant them into the straw bales I always include worm castings in my potting mix along with compost, Dolomitic limestone and some tomato fertilizer. Big believer in the merits of worm castings since it doesn’t burn and a little goes a long way. Since it is not cheap I find the best deal is a 30 pound bag from my local hydroponics store.

[Rockoe10]

@habitat-gardener I had to take cuttings for the first time last Spring and some turned mushy. Someone on the forum told me to root them in potting soil and that worked perfectly. Just keep the soil really moist.

I agree, soil is the best way to root tomatoes. When I'm in the garden during the growing season, when i pinch off suckers, i just plop them into the ground and they take over pretty quickly. Nearly 100% success with daily watering in a mulched bed.

[Amateurinawe]

well [mention]Rockoe10[/mention] that sounds like a big thumbs up approach, i shall give that a go...

[zeuspaul]

I tried both ways and had better luck in water. I placed a cutting in water and waited for the roots to be about 1/2 inch and then planted in small pot to establish the roots before planting in the garden. I did this mostly for seedlings that had experienced damping off.

[Amateurinawe]

@[mention]zeuspaul[/mention] me too, that's the way I've always done it. I'm gonna give both a go.

[AKgardener]

I started mine in February last year indoors thinking it would give me an edge but it was disaster for me they took their time and got stunted and didn’t produce until end of season. This year since our last frost date is June I’m gonna start them the last week of March my husband bought me a 20 foot green house and heat lamps to keep in warm so now I can move them out side properly and get a good start . I had my garden redone and they started at the beginning of October so they still need to add soil in spring gonna be behind there.I also start in small pods and use worm castings until they are bigger