How to start tomato seeds indoors

Get a start on the season by starting tomato seeds indoors

Here in Vermont, Town Meeting Day, the first Tuesday in March marks the day to start vegetable seeds.

I always start tomato seeds indoors because the growing season is so short here.

After abandoning vegetable gardening for flower gardening years ago, prices, concern for the availability of fresh produce, and wanting to fill my larder sent me back to vegetable gardening. That, and we can eat our weight in salsa and tomato sauce.

It took a little doing, some plowing, and some fencing off against wildlife, but we managed to create a good-sized spot for vegetable gardening. Because our growing season is so short, I start vegetable seeds indoors.

Last year, we planted about 50 tomato plants, pepper plants (all hot!), zucchini, summer squash, cucumbers, green beans, lettuce, and swiss chard. Those with a longer time to fruit, like tomatoes, get started indoors.

The soil is really rocky here, and root crops end up stunted and have funny shapes. Although, I might try beets again this year…

Oh, and I planted a dozen beautiful Brussels sprouts plants last year and got only a handful of Brussels sprouts, but one plant was actually a cabbage, so I had that.  I’ll have to research where I went wrong.

Quality seeds and dirt make the best start

If you’re going to the effort of starting vegetable seeds indoors, buying cheap seeds wastes time, soil, transplant pots, and the hopes for a productive harvest. It really pays to buy high-quality seeds that will germinate and produce robustly.

I highly recommend High Mowings seeds and other supplies from Gardeners’ Supply.  You can find all the seeds, grow lights, soil, and set-up you need. And they have experts to answer your questions.

Plus, they support some very important food and education causes. As they say, they are “a company of gardeners.” I love that.

I always joked that I was the only person on earth who couldn’t grow zucchinis but last year proved me wrong, and I had to pull out my recipes for cooking and canning zucchini.

Thanks to an abundance of cukes and zucchini, I have relish and dill pickles for years. Dilly beans, too.

But the salsa and spaghetti sauce were gone in February, so I’ll try to correct that imbalance this year. It’s not all skill (ha!)—the weather, bugs, critters, and luck mostly affect my crop yield.

Check out this post on tomato worms! How disgusting! But the ducks thought they were the tastiest treats ever!

The seed-starting process

This is how I start vegetable seeds. I got started a little late this year, on March 15^th, to be exact.

 I’m starting the Beefsteak, Brandywine, Better Boy, and large cherry tomatoes, and my son is starting the peppers and Roma tomatoes.

I bought peat pods this year because I saw them on sale, but seeds can be planted in egg cartons, in eggshells, and many other “vessels.” It saves time and cuts waste if the “vessel” they are planted in can become part of the transplanting process.

Using the directions, I wet the pods thoroughly and waited a couple of hours for them to fully expand. I had parts of a sprouting set-up, so I set some pods in trays with individual holes, and some went directly onto a piece of felt on a tray.

The felt holds water that the pods soak up. The other pods soak up water that I add to the bottom of the tray.

After spreading the seeds out, I use one of an old pair of chopsticks. I “stick” two seeds to the bottom by gently touching the chopstick to the seeds and depositing them into a pod.

Some day, I expect that I’ll be optimistic enough to put one seed per pod. It probably will help cut down on legginess, too. Right now, I do it to hedge my bets that I’ll have one strong plant and not waste the dirt on a seed that doesn’t germinate.

I gently tap a tiny bit of dirt over the seeds. I reuse some plastic lids from a previous seed-starting system to help keep the seeds warm and moist. Then, I label and date the tray, and that’s it!

The trays go in the south window, where I supplement the sunlight with longer artificial light from a grow lamp. Even though I have a warm southwestern-facing window, the light falls far short of the six to eight hours of sunlight recommended. Sixteen hours is even better.

And just like that, the sewing table in the southwest window becomes a greenhouse. Yes, that’s snow outside the window…

Keeping seedlings from becoming leggy

Whether this is your first time starting vegetable seeds or your hundredth, sometimes, seedlings seem to sprout up inches, literally overnight. How can you prevent leggy seedlings? There are a couple of tricks that help.

Legginess can result from too much water, too much heat or plants desperately reaching for sunlight.

First, be sure to use a grow light. You can go all-out and devise a hanging light or buy a clip-on style if you aren’t sure you’ll use the same setup every year. That will give you flexibility both in where you use it and to which plants you direct it.

Both of these are clip-on lights—one was clipped to the magnifying light I use for sewing (because I placed the plants in the south window on my sewing table) and the other is on my growing rack.

 

During germination, temperatures between 75 and 80 degrees are best. However, seedlings like temperatures of around 60 to 75 degrees during the day and 55 to 60 degrees at night. The containers with the newly planted seeds can be placed on heating mats to aid in germination, but after that, try to be conscious of too much heat.

Watering from the bottom up helps, too.

When to transplant new seedlings

It’s March 28^th, and the seeds have germinated!

I anxiously awaited the first tiny sprout but still patiently waited for the second set of true leaves, which was my cue to think about transplanting to bigger pots.

Don’t wait until they get leggy, thinking that they’re having a vital growth spurt.

Gently move the seedlings to larger cups or pots. Bury them almost to the lower leaves. They will keep them sturdy and well-nourished for the next phase.

That’s why these transplanted tomato seedlings look smaller than before I transplanted them.

Last year, we went a little crazy, and after transplanting only the strong plants, I still had dozens of tomato and pepper plants that I put out beside the road, free for the taking.

I hope it helped to feed some families last summer during the pandemic, and I hope I can do it again this year.

Hardening off seedlings

Even once we plant up here in Vermont, the weather can be a little unpredictable (by that, I mean chilly).

Anything transplanted into the garden MUST be hardened off to acclimate it to the outside temperatures and give it the best chance to survive.

The process of hardening off seedlings is simple. The trays go outside, away from strong winds and harsh sun. First, they go out during the day only. Then, when they’re a little tougher, they go out 24/7.

A gentle breeze helps to toughen the plants. Some people use a small fan to create a breeze.

Once my plants are a few inches tall and have study secondary leaves, I gently run my hands over them, “brushing” them lightly every time I go by them.

Planting the garden

Planting can’t be explained in a few sentences, so I’ll write a whole new post to describe how and when I plant the garden.

Saving seeds for next year

I have never done this. Although, I have to say that every year, tomato plants grow from the compost bin that I transplant into the garden.

Do you save seeds from the plants you harvest? Which ones? How do you do it?

Leave a comment, and we’ll be in touch. I’d love to learn how to do this and will be happy to pass on your tips!

Now that you will have all those tomatoes, you’ll need recipes!

Here are two easy tomato recipes to start with. Try my fire-roasted salsa and tomato confit that I use in yummy bruschetta.