How to Grow 184 Varieties of Heirloom Tomatoes from Seed (Without Losing Your Sanity).

I'm dreaming of tomatoes.

How to Grow Heirloom Tomatoes from Seed @Garden Delights.

Sometimes, my dreams are perfectly lovely. Rich, delicious Black Krims, sliced to show off their fabulous color. Sweet little Chocolate Cherries, popped off the vine and eaten like...well, chocolate cherries. Gorgeously striped Big Rainbows, so pretty and delicious that it's impossible to believe they're actually healthy. White Queen, divinely different. I fantasize about the many ways to devour each variety--Bruschetta! Caprese! Salads! Sauces!--particularly when we've been tomato-starved all winter.

How to Grow Heirloom Tomatoes from Seed @Garden Delights.

Then, there are the other dreams. Dreams where thousands of tiny seedlings grow in the greenhouse and demand new homes. The first seed sprouts overnight. Within two days, every propagation tray is filled with tiny, adorable seedlings. And they grow. And grow. The first true leaves appear. I raise the grow lights on the chains, and they grow more. Soon, every spare second is spent in the greenhouse, potting up. More soil, more pots, more seedlings...and I wake in a panic, wondering how it will all get done, and if anyone will buy them.

Every year, it's the same. I overplant. And every year, I experience the same heart-stopping moments of panic, eventually practicing my yoga breathing until I remember that I always finish in time for the planting season. Every year, Peter reminds me not to plant so many varieties. But how can I possibly resist seeds with names like 'Golden Sunray,' 'Jaune Flamme,' 'Missouri Love Apple,' and 'Ananas Noire'?

Every year, a few more varieties find their way into the mix, because I MUST try them.

It's an obsession.

This year, with 184 varieties of heirloom tomatoes growing in the greenhouse, as well as heirloom peppers, herbs, flowers, and many other seedlings, I might need to admit that Peter was right.

You know, I hate when he's right.

It would be much easier to plant 100 seeds of 20 varieties, but where's the adventure in that?

Plus, my goal with Garden Delights--the nursery, that is--is to offer the odd heirlooms. The white tomatoes, the plants with pretty foliage, the multi-striped, delicious and beautiful varieties. I'd always rather grow interesting tomatoes than pedestrian, red, round fruits. (The Garden Delights store will be open soon.)

Still, most sane gardeners want to grow only a few tomato plants for their garden. While it might seem counter-productive to offer seed-starting tips when I own an heirloom plant nursery, I honestly believe it's a life-changing experience to savor a homegrown tomato from a plant that you started as a seed. There's just something validating about planting a seed, watching it sprout, nurturing the seedling, planting it in the garden, and ultimately harvesting the fruit. It's life-affirming.

(OK. Did I go too far with the life-affirming part? Sorry. I really am that passionate about growing tomatoes.)

Try it. I promise, it's soul satisfying.

Seed-starting mix
Spray bottle filled with water
Plant tags and permanent marker
Heat mat (optional, but highly recommended)
Adjustable light source (I use shop lights on chains with Daylight colored fluorescent bulbs.)
3-4" containers (I use biodegradable pots)
Organic potting soil
Fish emulsion fertilizer
Authentic Haven Brand Moo Poo Tea
Watering can

Growing tomato seeds provides nearly instant gratification. First of all, you've most likely spent the gloomy winter months highlighting and dog-earring the many seeds catalogs that found their way into your mailbox. Make your list of the prettiest, yummiest-looking tomatoes you find--and order those seeds, pronto. Seriously. Many varieties sell out. I ordered my seeds in January, and three varieties I wanted were gone.

How to Grow Heirloom Tomatoes from Seed @Garden Delights.

If you want to try several varieties, that's great--tomato seeds remain viable for up to five years if stored in cool, dark, dry conditions. Order what you'd like, then remember to tuck the remainder away properly. Or ask a friend if they'd like to share seeds, which will save you both money, and you'll still have plenty of seeds left over for future seasons.

My favorite seed sources are Baker Creek Heirloom Seeds, Seed Savers Exchange, Botanical Interests, and Renee's Garden. I always select organic, heirloom seeds (with the exception of one hybrid: Sungold. It's delicious, and it earns its place in my seed stash.) Expect to pay about $2-3 per pack of seeds, with about 25 seeds per pack, on average.

Growing Supplies.
Because I grow thousands of seeds, I use trays that allow many seedlings to grow together in a relatively small space. These propagation trays are available in different cell sizes. The ones I use are 128-cell trays, with a clear plastic dome cover to help retain moisture and a solid under tray to keep water from leaking. You can find these at Johnny's Seeds.

If you're starting seeds in recycled containers or old nursery pots, clean and disinfect the containers to ensure that your seedlings stay healthy. I reuse my trays each year, and each year I kick myself in the spring for storing them over the winter without cleaning them first. You'd think I'd eventually learn, but instead I spend almost a week in early spring scrubbing trays and disinfecting them with a bleach solution. (10% bleach, 90% water.) Honestly, I'm not terribly scientific about the ratio of bleach-to-water. I pour a good splash into the sink and add water. It seems to do the trick. I almost always ruin a shirt while scrubbing trays, so apparently there's enough bleach to kill bacteria and fungal diseases, too.

(I know you're going to want to skip this step, because who wants to waste time scrubbing trays, right? Please don't. You'll be so sad if your plants die because of a lingering disease on the tray. Google "damping off," and you'll see what I mean.)

The growing medium is also important when starting tomatoes. Use a disease-free, light, soilless seed-starting mix. You can find it at any big box store or garden center. Again, you want to give your babies the healthiest home so that they can grow big and strong. Garden soil also can harbor disease, which can kill tender seedlings.

Of course, you'll want a water source nearby while you sow seeds, and you'll also want to label your seedlings. I ran out of my usual plant markers this spring, and the store wasn't going to restock them for several weeks. So, I improvised. I washed and disinfected a gallon milk container, then cut the container into strips. Finally, I cut each strip into approximately two-inch sections, and voilà! I had at least 100 free plant tags. Use a permanent marker when labeling your seedlings.

As you're gathering supplies to start seeds, pick up the things you'll want for potting up, too. I use OMRI certified, biodegradable pots for our plants, but you might want to use three or four-inch up-cycled containers. When you transplant the seedlings into their larger containers, you'll want a good, organic potting soil for their new home as well.

Finally, after all the seedlings are transplanted, I use diluted fish emulsion to fertilize the plants. It smells horrific. I'm sorry. Still, it really does work well to give the tender seedlings a gentle boost of nutrients without burning delicate roots. After the first application of fish emulsion, I'll use Annie Haven's Moo Poo Tea to enrich the soil and for foliar feedings. It's gentle on seedlings, and it provides perfect micronutrients for the plants.

Getting Started.
You've gathered all of the supplies, your seed trays or containers are sparkling clean, spring is in the's time to sow those tomato seeds!

The general rule is to wait until about 6-8 weeks prior to your last frost date before starting seeds. I usually add an extra two weeks to that date and start them about 10 weeks prior to the last frost. For the last two weeks, I have the plants spend part of the time outside the greenhouse, hardening off, so that they're well-adapted to the environment before planting in the garden. But that's a story for another day. Just know that you'll want a few weeks to do this, too, or you'll have unhappy, stressed plants.

Sowing Seeds.
Moisten your seed starting mix before adding it to the trays. I pour the seed starting mix into a Rubbermaid container, then add water to it, making certain it's well saturated--but not dripping. (The best way to do this, I find, is to just get in it with my hands and mix it up.)

Use a cup (or your hands) to spread the moistened seed starting mix into the trays, patting it lightly into the cells or containers to remove air pockets. Fill each cell or container about 3/4 full.

(I typically fill all of my trays before I start sowing, since my hands are already wet and dirty.)

Now, the fun begins--time to sow the seeds! Make sure your hands are clean and dry when handling the seeds, so that you don't contaminate any seeds that you want to save for the following year.

I usually sow two seeds per cell, simply because I'm a glutton for punishment. (Actually, I do it in case there's a germination problem and to save space.) If you're smarter than me and only sow one seed per cell, potting up is quicker. Stay tuned for potting up...)

Label each variety as you finish sowing it to avoid confusion.

Once you've finished placing the seeds in the cells/containers, cover with about 1/2 inch of the seed starting mix. Add a bit of water to settle the mix and seeds. (I use a spray bottle to mist the seed tray.) Place the plastic dome on top of the tray to preserve moisture.

Growing Conditions.
Tomatoes and peppers like warm soil to germinate, and a heat mat speeds germination. By using a heat mat, my first tomato seedlings appeared within 24 hours, and all of the seedlings were up in two days. Some people say heat mats are unnecessary, but I'm a believer in them.

I place the seed trays under the grow lights immediately, because that's how the greenhouse is arranged--heat mats are directly under the lights. As soon as the first seedling appears, it's time to make certain that the new green babies have a good light source.

Growing Station for Seedlings @Garden Delights

Many people start tomatoes using only the light from windows, which can result in spindly, leggy, weak plants. Using an inexpensive set up like we have--built from 2x4s with shop lights on adjustable chains--helps ensure strong, healthy plants. With a light source only a few inches above the plant, it doesn't need to stretch to seek light, as it does in a window. As the plant grows, the lights are easily moved up to accommodate them.

Most importantly, don't allow the seed trays or containers to dry out. Be careful not to over water, too. You'll want a happy balance of moist, but not soggy, seedling containers.

As the Tomato Plant Grows...
Remember Biology 101?

How to Grow Heirloom Tomatoes from Seed @Garden Delights

Those first leaves aren't true leaves. They're the cotyledon, or seed leaves. You'll see the difference in the true tomato leaves as they appear.

How to Grow Heirloom Tomatoes from Seed @Garden Delights

One of the easiest ways to encourage strong stem development in your plants is to rough house with them--just a bit.

How to Grow Heirloom Tomato Plants from Seed @Garden Delights

Each day, brush the seedlings a few times with your hands or a ruler, gently moving them to mimic wind. Some people use a fan instead, but I find that the fan causes the soil to dry out too quickly, requiring more watering. Several times a day, I brush the seedlings, and I can see the stems getting thicker and stronger. Do this even after you transplant.

Once your babies have two sets of real leaves, it's time to move them to their new homes.

Potting Up.
Now, the fun begins. If you've only planted one seed per cell or container, you win the prize of an easy, quick transfer to the new container!

How to Grow Heirloom Tomato Plants from Seed @Garden Delights

However, if you have multiple seedlings in one cell, you have two options: pick the healthiest, strongest seedling, and murder the others--a quick pinch at the soil line or snip with tiny scissors will do the deed. Or, if you're like me and can't stand the thought of baby tomato plants meeting untimely deaths, then you carefully separate the seedlings.

How to Grow Tomato Plants from Seeds: Potting Up.

I use an old fork to remove them from the cell, then I gently tease them apart at the roots.

How to Grow Heirloom Tomato Plants from Seed: Potting Up.

I'm not going to kid you--it's time consuming. Once you've done a few hundred, though, the process goes more quickly. (Feel free to stop by the Garden Delights greenhouse in the next few weeks to practice, if you'd like.)

How to Grow Heirloom Tomato Plants from Seed: Potting Up.

I fill a tray with my biodegradable pots, then fill each pot about 1/4 full of organic potting soil.

How to Grow Heirloom Tomato Plants from Seed: Potting Up.

Placing the seedling carefully into the container, I add more soil until the stem is almost completely buried, leaving only about an inch or two exposed. By burying most of the stem, the plant will form additional roots along the stem in the soil, making for a nice, sturdy plant.

How to Grow Heirloom Tomato Plants from Seed: Potting Up.

Add a plant marker in the new container, water gently, and repeat. And repeat. Repeat a few thousand times, if you're obsessed with tomatoes, like me. Once your tray is full or you've finished potting up your few containers, place the plants back under the grow lights. (I keep the heat mats on, too, until the weather is consistently warm.)

As the plants grow, move the lights accordingly. I like to have the lights no more than two inches above the plants.

Getting Ready for the Big Move.
The weather is getting warmer, and you've consulted your calendar for your last frost date, which is only a few weeks away. (Check here to find your projected last frost date. Just enter your zip code.) As you prepare to move your babies into their permanent home, take the time to acclimate them to the outdoors, also known as "hardening off."

Find a shady, sheltered location outside. You want to avoid direct sunlight and wind at first. Each day, place the plants outside for a few hours, gradually moving them into the sun a bit more each day. After all, tomato plants need full sun to produce fruit, but your babies have been pampered--like a human baby, they'll burn if exposed to sunlight too quickly. Your goal is to toughen them up by gradually exposing them to the great outdoors and the elements. Each day, give them a bit more outside play time, a bit more sun, a tad more wind exposure. By the end of two weeks, you'll have strong, resilient plants ready for their new home in your garden.

(Of course, keep up with the watering. They'll be thirsty babies with all this outside play time.)

Congratulations, my friends. You've taken a teeny, tiny seed and created a beautiful plant that can nourish you, your friends, and your family. When we get a little closer to the last frost date in SC (mid-April here), we'll talk about putting those babies in the garden.

For now, though, it's time for me to head back to the greenhouse.

How to Grow Heirloom Tomato Plants @ Garden Delights.

The seedlings are calling.

Have you ordered your tomato seeds? What varieties will you grow this year? Do tell...I might need to add some new varieties next year!



tagged under: heirloom tomatoes, plants, tomato, growing from seed, potting up, Growing gardens