Planting Tomatoes

 Planting Tomatoes Outdoors

Tomato plants are essentially tropical plants, needing warm days and cool nights. They prefer soil temperatures between 70°F and 75°F. They (drop)blossoms if air temperature is cooler than 55°F or hotter than 90°F and are very sensitive to frost, which blackens and kills them.

Tomatoes need at least 6 to 10 hours of sun daily plus some afternoon shade in really hot climates.

They accept almost any kind of soil, as long as it has lots of organic matter in it to help it hold moisture and drain well and is on the acid side (pH 6.0 to 7.0).

Add organic matter such as peat moss, chopped leaves or compost to lighten and loosen clay soil or plant tomatoes in raised beds to improve soil drainage.

Mix in some all-purpose slow-acting organic granular fertilizer or a fertilizer product for acid-loving plants when preparing the soil. Follow directions on the package label.

Avoid Problems When Buying Tomato Seedlings

When buying tomato plants at the garden center or farmer’s market, look for deep green leaves and for stocky, short plants that look healthy. Check the pot to see if the soil is moist and rich-looking. Pull one or two out of their container and see if the plant is root bound.  Do not buy wilted plants or plants with yellow leaves. Especially be sure you know which of your tomato plants are determinant (grow 4 or 5 feet) or indeterminant (grow over 7 feet).  And, don’t forget to protect your plants from the elements on the drive home. Translation: Don’t put them in the back of an open pickup and then fly home on I-5.


First There Is Hardening Off

You should not even think of planting tomato seedlings until the soil temperature is at least 65 degrees; 70 degrees is better.  When the soil temp is okay then you need to bring your seedlings outside during the day and then bring then back inside at night for at least two days.  This helps the seedlings get used to real sun and the breezes. 

Tomato Planting Amendments

Critical New Products To Make Planting Tomatoes A Huge Success

There are three new garden products and one old one that have become essential at planting time to our success in growing wonderful tomatoes.

Compost – Available forever, compost is incredibly valuable when included in the soil where you are planting tomato seedlings – we use a half a cup per plant. 

Myke – Myke ( contains mycorrhizae which are beneficial fungi that attach themselves to the roots of a plant and literally double the size of the plant’s root system in a few weeks.  This significantly increases a plant’s access to water and nutrients.  It’s crazy not to use this product – a tablespoon per plant on the root ball and in the planting hole. 

Actinovate – Actinovate ( is a biological organic fungicide that has the very powerful ability to prevent virtually every fungal disease that affects tomatoes including early blight, fusarium, verticillium, and late blight.  You spray it on the root ball and on the plant at planting time and then spray the plant every two weeks throughout the season.  Available on 

Vegetable Thrive – Thrive ( contains Microbial Soil Bacteria and Mycorrhizal Fungi; two groups of beneficial microbes found only in very healthy soil with an organic content of at least 5%.  Most of us do not have soil with 5% organic matter or higher so Thrive provides the services of critical beneficial soil microbes as we work to get our soil up to organic snuff.  Available on  Spray on plants at planting and then spray plants every three or four weeks throughout the season. 


Steps for Transplanting Seedlings

  1. Water seedlings well 1 to 2 hours prior to planting, to keep their rootballs intact during the transplanting process.
  2. Plant on a cloudy day or in late afternoon or evening to protect seedlings from the hot sun while they cope with transplant shock. The soil is cooler and the relative humidity higher then, reducing moisture stress on the new plants.
  3. Space transplants 1½ to 2½ feet apart. With a trowel dig individual holes a bit deeper than the seedling’s rootball or container. Deep planting encourages roots to form along the buried stem, increasing the plant’s capacity to take up water and nutrients, resulting in stronger plants.
  4. Gently coax each seedling from its container, set it in its hole and fill in with loose dirt. Press the soil gently around the main stem. Water transplants generously and then do not allow them to dry out.
  5. Drench the soil around each seedling with Actinovate and with Thrive
  6. Apply an inch of organic mulch around the seedlings.  After they get large enough add mulch until the depth is 3 to 4 inches. 

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