How To Trench Tomato Plants – Horizontal Planting

Six ripe sweet tomatoes ready to harvest.

Burying a part of your tomato plant stem is essential to encourage a stronger and broader roots system. Doing this will support the heavy loads of tomato fruits.

However, burying the stem of a very tall tomato plant will make its roots end up in the colder zone of the soil. The low temperature can cause the root ball to stop growing and it will slow down plant growth while trying to adjust.

Planting tomatoes horizontally in a trench is the answer. This will surely keep the roots in a warmer zone while allowing it to produce more with limited disruptions. Check out the guide below to see exactly how you can trench your tomato plants.

Tomato Trench Planting: Step-by-Step Guide

You’ll need:
  • Shovel
  • Wheelbarrow
  • Fertilizer
  • Stakes (support)
Step-by-Step Guide:

  1. A horizontal trench is better compared to a hole for each plant. It should be a little bit deeper for the roots to go.
  2. Toss an adequate amount of fertilizer into the trench and mix thoroughly with the soil using your garden fork.
  3. With the use of a garden hose, water the trench until it is completely saturated.
  4. Snip off the lower leaves from the plants leaving only 4-5 leaves at the top cluster.
  5. Gently mold the soil around the root system of the plants and lay on the side of its trench.
  6. Bury the stem about 2-3 inches of the soil up to the remaining leaf cluster.
  7. Secure the stem by slightly pressing the soil around the stem to avoid breaking them.
  8. The newly planted tomato plants may look like they have no energy, but they will come back to their healthy vigor after a day or two.
  9. Install plant support of your choice, avoiding to damage the newly buried stem.

What is the Ideal Size of the Trench?

If your seedling is 8 inches tall and you want to leave 2-inches to stem above the soil, you can dig a six-inch deep trench as the length of the root ball. Add the measurement of how much you want to bury the stem.

Fertilizers for a Trench

Types of Fertilizers

  • Slow-release fertilizer is essential for horizontal planting.
  • Fertilizer should be high in phosphate and potash feed. (the need to fully charge the nutrients over the winter months for the coming season)
  • The slow-release nitrogen content must not seep in cold soil in the winter.

Directions for Use

Storing and Disposal

  • To prevent moisture penetration, fold over the bag if not fully used.
  • Store in a cool, dry place. (avoid damp conditions and direct sunlight)
  • Dispose of safely if the bag is empty.
  • Wash your hands properly after each use.

Installing The Stakes For Your Tomato Plants

Tomato plants with stakes in the field.

One of the simple methods to support tomatoes is the use of staking. Staking provides much support in growing tomato plants in your garden.

Advantages of Tomato Staking

  • Growing more plants is possible in the given area with the help of staking.
  • The fruits are safe from rotting because stakes keep the vines and fruits off the ground. 
  • The continuous pruning in your staked tomatoes makes the fruits ripened ahead of time, resulting in an early harvest.
  • Working around the plants and picking tomatoes is a lot easier. 

Disadvantages of Tomato Staking

Cracked ripe tomatoes due to lack of water.

  • Staking and pruning tomato plants take effort and time.
  • Tomato plants with stakes are vulnerable to sunscald problems, the rot of blossom end, and cracking.

How To Stake Your Tomato Plants

Tomato plants with fruits tied with a cloth strip.

  • Place the stake on the prevailing downside of the plant (the tomato plant can lean against it when the wind blows hard)
  • Stakes that are 6-8 inches high are adequate for most tomatoes, but shorter stakes about 4-5 feet high are better.
  • Install the stakes right after planting the seedlings.
  • Drive the stakes into the soil about a foot or two, and 3-5 inches away from the stem.
  • Remember to avoid staking the side of trench-planted tomatoes.
  • Tie a cloth strip or a nylon-string securely into the stake and slightly loosen the knot around the plant.
  • Secure by adding more ties needed as the plant climbs up the stake.

What About the Total Yield?

A smaller variety of tomatoes ready to harvest.

  • Tomatoes without stakes yield more fruits compared to the plants that have stakes.
  • Regular pruning off of branches and side shoots reduces the leaf surface of the plant, which is the plant’s food production. 
  • Less leaf surface also means less food provision resulting in a lesser total yield.

The Use of Mulch

Hay used as mulch in the tomato garden.

Mulching with the use of hay or grass clippings is necessary for the plants that use stakes. Mulch is responsible for retaining soil moisture.

Staked plants need more water compared to the plants that have no stakes.

The plants are more susceptible to sunscald as they are tied up and exposed to the sun and drying winds.

What Exactly is Trench Planting?

Tomato grower creating a trench for the seedlings.
Image by:

Trench planting is easy to maintain. Unlike raised beds, gardeners dig the ground horizontally to place fertilizers before planting the crops.

The process is complete with the use of a small amount of topsoil to backfill the trench up above ground level.

Benefits of Trench Planting

A gradual break-down of organic materials placed in the trench adds nutrients to the soil. Organic matters can help retain the soil moisture allowing you to water your plants less.

Some gardeners use the technique of composting and soil incorporation. Trench gardening provides all-year-round gardening in warmer climates.

Basic Design of The Trenches

Tomato seedling laid in a trench.
Image by:
  • Build trenches along the outlines for optimal performance.
  • Mark the line before you start shoveling.
  • In digging the trench, lay the soil at the edge of the channel.
  • Plant the crop between the trenches.

Trenches can be continuous or intermittent. Gardeners prefer continuous design if they aim for moisture conservation, particularly in the region with low rainfall.

On the other hand, interrupted trenches are preferred by gardeners in the areas with high rainfall.

The slope of the field determines the ideal distance between trenches. The steeper ground needs less distance.

Water flow during heavy rainfalls can be dangerous, so building drainage and waterways are necessary to control and prevent excess water.

Prevent Pesky Pests

A green worm eating the leaves of a tomato plant.To prevent pesky pests and maintain the fertility of your garden, leave approximately 20 inches between rows. The purpose of this is to give plants more room to grow while reducing the competition for moisture and nutrients.

The use of companion planting works well in trench gardens. You do this by sowing different types of leafy crops next to your tomato plants that are beneficial to each other.

The Costs

Soil conditions matter when calculating the costs of the filling materials for your trench, along with the labor needed.

Tools like stakes, shovels, picks, and crops are the primary tools you’ll need in building your tomato trench garden. Otherwise, you will need a tractor depending on the steepness of the field.


For achieving its high outputs, remove weeds from the plant surroundings and always keep the soil uphill in the trench.

Frequent repairing of the edges is required until the roots of your plants are robust and stable.

Final Thoughts On Trench Planting Your Tomatoes

To ensure your tomato plants can carry the weight of those yummy fruits, a solid foundation to grow the plants up, robust and tall is essential.

Trenches are a technique design to counter common problems in most areas with much rainfall conditions. 

Continuous trenches are suitable for dry areas, while the intermittent system is an exceptional help in regions with consistent rainfall.

There you have all the information you now need to know about how to trench your tomato plants the right way.

Did I miss anything? Tell me about your experience with tomato trench planting. Please don’t hesitate to write in the comment section below. We’re always glad to hear your thoughts

About Benita Abucejo

Hi there! My name is Benita Abucejo. What can I say? I truly love spending my days in the outdoors, specifically in the garden. Gardening has always been a strong passion of mine since I was a little girl. It has brought me so much joy and happiness that it is definitely safe to say that I will be a gardener for life. For a period of time, I was able to work with people who are into home gardening and I found it to be quite beneficial to my physical health, as well as my mental well-being. Here at Seasonal Preferences, I am going to share with you my experience and ideas so that you can fulfill yourself with the same satisfaction and happiness. Of course, if you have ideas, I would love to hear those as well! Being creative in the garden can really be quite fascinating so let's share our experiences and be the best gardeners we can be. With that being said, thank you for dropping by and please leave me a comment on one of my posts if you would like to get in touch!

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