How to Plant Tomatoes (and Get the Best Root System)

Homegrown tomatoes (and basil) are the reason most of us began growing food in the first place. Though some people direct sow their tomato seeds, most begin the season with transplants. Tomato transplants are a little different than other vegetables — there are some simple tricks that can improve their root system and vigor in your garden. This photo tutorial will show you how.

If you just came for the produce pictures, check out How to Increase a “Tomato Problem” (with Gratuitous Photos).

Photo Caption: You can increase your tomato yield with the method you bury your transplants at the start of the season. This mix of heirlooms harvested in 2009 began in home-grown seedling trays.

First, decide if you’re going to direct sow from seed or if you would like to use transplants. One factor is your season — you need at least 4 months between your spring frost-free date and your first frost date in the fall in order to successfully direct sow tomatoes. Tomato diseases are another thing to consider. In many areas a head start from transplants will mean that you get a good crop before late summer pathogens attack your plants. Personally, my main reason for using transplants is pests. I find that tall, thick-stemmed transplants are less tempting to slugs, snails, cutworms, and pillbugs than newly emerging fragile seedlings. I often struggle to get direct sown crops to flourish when these species are abundant.

Next, make sure you are planting in an ideal tomato location. Full sun is crucial. If you have 6 hours or less of sun a day you’ll have better luck with small-fruited tomatoes like cherries. Big, flavorful tomatoes need lots of sun and plenty of leaves to photosynthesize with. Loamy soil, high fertility, consistent irrigation, strong support (cages, trellising), and some kind of mulch are also recommended.

Once you’ve decided on seeds or transplants and a planting site you can put them in the ground on or after your area’s frost-free date. In addition to throwing some fertilizer into the planting hole you can give your tomatoes an edge by planting them deeper than they were in their pots. Most vegetables suffer when their crowns are buried too deeply, but tomatoes thrive on it because they can produce roots all along the length of their stems.

If you decided to direct sow from seeds you can still use this method. Instead of seeding on a level garden bed surface, dig a shallow pit (about 6″ deep) and sow your seeds at the bottom of it. Once your seedlings have grown at least 10″ tall you can fill in the soil so that the tomato has a larger length of buried stem. Alternately, you can try leaning a seedling on its side and covering it with soil — but this is risky since tomatoes are often brittle and will snap.

For transplants, the photo tutorial below demonstrates how to plant them in order to maximize root growth. Click on the image to see a larger version.

Photo Caption: My photos are of some overgrown "replacement" tomatoes I put in to compensate for cutworm losses. This method works particularly well for tomatoes that have become lanky after spending too much time in a pot. First, dig a hole where you can lay the seedling down at a 45 degree angle when you plant it. Remove the lower leaves (make sure at least 2 sets of true leaves remain at the top).

Photo Caption: Set the transplant at the 45 degree angle in the hole and make sure the true leaves are above the surface. Most people think tomato roots grow downwards but they tend to spread horizontally. The extra buried stem will allow the tomato to produce more roots in this manner.

Photo Caption: Bury the transplant up to the true leaves. This will become the new "crown" of the plant. Don't worry if your tomato looks like it is laying on its side -- within one sunny day it will right itself into a vertical position again.

A thorough list of tomato seed sources can be found here. Transplants are frequently available from farmers markets (they’re a good early season product while farms wait for their summer crops to come in). Also, locally owned feed & seeds usually have better veggie transplant prices than big box stores.

Eliza Lord

I'm a Greenville, SC native (the Appalachian foothills) who wears the hats of Greenville Master Gardener & Upstate Master Naturalist. I love to write about food and sustainability.

9 thoughts on “How to Plant Tomatoes (and Get the Best Root System)”

  1. Curbstone Valley Farm - May 11, 2010 12:02 pm

    We’re grew ours from seed this year, but they were seeded indoors in January. Transplanting the seedlings deep is definitely key! Oh, and thanks for the reminder…its time to build our tomato cages!
    .-= Curbstone Valley Farm´s last blog ..It’s Not Easy Being Greens =-.

    1. Sustainahillbilly
      Twitter: appalachianfeet
      - May 12, 2010 10:28 am

      I’m sharing a vegetable garden with friends this year and I think this may be the first time all my tomatoes were caged the moment they went in the ground. I’m so relieved — I don’t know how many times I’ve procrastinated until they were too big to slip a cage over easily. It’s no fun to try to manipulate the brittle stems into the cages!
      .-= Sustainahillbilly´s last blog ..How to Identify a Northern Water Snake =-.

  2. Meredith - May 11, 2010 3:01 pm

    I’ve never tried the 45 degree angle, and may do so on our last few transplants. Thanks for the tip! I always bury them deeply, and last year I tried the trench method with a few seedlings, but those plants didn’t do quite as well as the regular deep-sown ones. (That could, of course, be due to a variety of factors, including soil fertility, sun exposure, and plant variation, because we’re not talking about a proper scientific experiment.)
    .-= Meredith´s last blog ..a hint of joys to come =-.

    1. Sustainahillbilly
      Twitter: appalachianfeet
      - May 12, 2010 10:31 am

      Uhoh, you’re failing in your duty as a gardener to speculate wildly and proclaim your hypothesis as hard truth! πŸ˜‰
      .-= Sustainahillbilly´s last blog ..How to Identify a Northern Water Snake =-.

  3. Anna - May 12, 2010 8:29 am

    My father lives in South Carolina in sandy soil on well water where it’s painfully dry and he can’t water. He told me that last year he set out tomatoes with a post hole digger, putting them quite deep in the soil so that only a tiny bit of leaves could be seen above the ground. And they thrived! I’ll bet if you have non-waterlogged soil (unlike us), the deeper you plant, the better!
    .-= Anna´s last blog ..Anna: On the garden locomotive =-.

    1. Sustainahillbilly
      Twitter: appalachianfeet
      - May 12, 2010 10:32 am

      That’s a great idea and tip, thanks for sharing it! I know people complain about heavy red clay but when I look at the alternatives I think it is a sweet deal.
      .-= Sustainahillbilly´s last blog ..How to Identify a Northern Water Snake =-.

  4. Sandra - June 3, 2010 12:53 pm

    Yum! Seeing all those tomatoes makes my mouth water; I am SO looking forward to fresh vegs!
    The first year we moved to the farm, I planted tomatoes by scratching out a scant few inches of soil and laying the tomatoes on their sides. They thrived, much to everyone’s amazement! Of course, I did throw the horse manure to them and not the rotted stuff either; it was fresh as fresh could be and the tomatoes still did wonderfully well.
    Just goes to show you, eh?
    .-= Sandra´s last blog .."I Send You Wings" =-.

    1. Sustainahillbilly
      Twitter: appalachianfeet
      - July 1, 2010 12:51 pm

      I love it when plants break the rules! Makes me feel like I’m breaking the rules, too. πŸ˜‰
      .-= Sustainahillbilly´s last blog ..How to Be Even More Excited About Home Than Wherever You Vacationed Garden Photo Essay =-.

  5. jalal saleh - April 9, 2014 6:10 pm

    I’m living in south Boushehr Persian Gulf and hundreds of hectares of land is cultivated tomatoes. Boushehr is dry and hot climate we need to produce tomato seedlings with roots strong . Resistance to hot winds., You can help me

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