Measuring Tomato Seedling Success

Reader Contribution by Ilene White Freedman
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It’s time. It’s time to separate the wheat from the chaff. It’s time for tomato seedlings to stand up and be measured. Are they fit for the job?

If you start your own seedlings under grow lights or in a window, you might be asking these questions of your tomato plants in the next few weeks. You’ve grown them from seed. You’ve nurtured them, fussed over them, watered them, provided the best lighting you could offer.  Even if they’re spindley, you might be a bit attached to your little babies by now. You’ve grown them from a pup, and now its time for them to go out in the world and establish some roots. The main question: Will they do justice to your garden?

Ideal Tomato Plant Measurements

What exactly will it take for these tomato plants to do justice to your garden? Your goal is 5-8 week old plants with pencil thick stems and pencil long height. The height doesn’t matter as much as the stem thickness. This will give the jump start that tomato plants need in a relatively short growing season as we have in the eastern US, at least. With only July and August as hot enough months to produce delicious tomatoes, the plants need a jump start of a couple months of indoor or greenhouse growth. Seed packets say 8 weeks, but I know my greenhouse does the trick in 5 weeks. They would be monsters by 8 weeks. Under grow lights, I bet it’s closer to 8 weeks.

When I meet a new gardener who is also starting tomatoes from seed, I offer some unsolicited advice. It goes like this: If you are blending the two arts — the art of seed-starting with the art of gardening, you should know if you are starting your garden with a jump start or at a deficit.

Seed starting can be tricky, especially under lights. After all, trying to replicate the sun is a lot to expect from a fluorescent light bulb. The sun is a beautiful amazing tool. When I moved from starting seeds under lights to our first greenhouse, the difference was incredible. Seedlings that were stretching for the light under my fluorescents were now growing thick and stocky under nature’s perfect grow light. So if you can, find a way to utilize direct sunlight. Check the Mother Earth News blog for ideas on constructing something really cool. Or, if growing indoors under lights, work on how low you can keep that light, raising it a notch as the plants grow. Otherwise, they reach and reach, all leggy and spindly (same thing).

Tomato Plants a Bit Leggy?

What to expect from tiny tomato plants? Tiny tomato plants, or long but skinny ones, may not survive the transplant. Or they may develop into nice plants and fruit, giving you hope, but they could be too late to catch the ripening season at all. Or maybe it works out fine, just a little late, missing the first month of harvest potential. But now you are well-supplied with information, so if your plants don’t make the grade this year, try ’em anyway, but go in knowing the possibilities. Maybe also buy ideal sized plants to go alongside them. It can be a year to experiment and compare. Worst case is a bumper crop.

Peppers and Eggplants

If you are going to be strict with your seedlings, let it also be with your peppers and eggplants. Peppers are slow to get started and need a longer season just like tomatoes. Eggplants need to be strong big plants before they go out and combat flea beetles, at least in our eastern region. Flea beetles will conquer a weak eggplant seedling and make its leaves into holey lace. We grow them strong and keep them under row cover until they flower. Then we take away the row cover altogether, flea beetles are no longer a problem, and then the pollinators can do their magic to the flowers. Starting with big plants makes all the difference in the world.

Cutting Some Slack

Greens, cabbages, root crops, and many others have a short enough season that they will endure a slower start and still give you a crop if the seedlings are little or spindly. Many often thrive when direct seeded into the ground, like beets, peas and beans, and lettuce.

Most new gardeners who hear my little lecture about separating the two arts say, “That’s some sound advice.” Milisa, a volunteer on my farm, listened politely then shrugged her shoulders. “So my tomatoes will be late, that’s fine.” At least they are all mine, was what her look added. I love that DIY gardener’s attitude, and I commend her. But gardeners should still know if that’s what they are in for, late tomatoes or not. Don’t be disillusioned and then a frustrated gardener, when it had less to do about gardening and more about the tricky art of seed-starting. Don’t quit, just be aware. Keep trying, keep tinkering and learning, and remember to separate the two arts, the art of seed-starting and the art of gardening. How? Separate the wheat from the chaff before you put those babies in the ground, or join Milisa and go for it anyway.

Ilene White Freedman operates House in the Woods organic CSA farm with her husband in Frederick, Maryland. She blogs about making things from scratch, putting up the harvest, gardening and farm life at, easy to follow from our Facebook Page. For more about the farm or their seedling sale in Maryland, go to