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Best Soil for Raised Beds: Grow Great Vegetables

Reginald is a retired educator with a passion for gardening. For the past 30 years, he has proven techniques and loves sharing with others.

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Best Soil for Raised Beds: Grow Great Vegetables

Gardening is great fun for young and old alike. This activity is both physically and mentally beneficial. From the design to the planting and ultimately harvesting your vegetables. This article deals with Best Soil for Raised Beds. Read further and learn about the ingredients that go into the best soil for a great garden.

Types and Sizes of Raised Garden Beds

The raised bed concept in the home garden is not a new idea. It does stand as a great option for the beginning or intermediate gardener. Raised beds in a vegetable garden have advantages over just planting in the ground.

  • A great option for anyone with limited space.
  • Various heights allow easier access to vegetables.
  • Raised beds organize and make a garden decorative.
  • Controlled environment for your vegetables.
  • The soil in a raised bed improves over the years.

Below are three of the most commonly used raised beds:

Wooden Boxes - the most popular of all raised beds. Lumber sizes come in 8’, 10’, 12’, and 14’ lengths. Widths are 6”, 8”, 10”, and 12”. This gives you a variety of sizes for your area. The most common size is the 4’ x 8’ raised wooden bed. It is highly recommended to purchase your lumber pressure treated. You will find that they will last for years.
Metal Tubs - galvanized corrugated steel construction. Not as attractive as wooden beds. It will last for years. Not as many size choices. Metal beds come in rectangular and circular shapes.
Concrete Blocks - Concrete blocks for raised beds is a lot of work to make them attractive. The first layer needs to be level. For this type of bed to be functional, two additional stacks may be required. Single open blocks measure 8”x8”x8”. Regular open blocks measure 6”x 8” x 16”.

First Layer - Yard Debris


Soil Ingredients for Your Raised Beds

Soil for your garden is like baking a cake. For the best cake, you need to have certain ingredients that go into the mix. When filling a raised bed, you need to think of it as a layer cake. And we do this by filling it with layers of material.

Below is a list of ingredients for our raised bed soil mix. Or - layer cake!
The first layer is the nonessential matter like small branches, sod, grass clippings. These materials are just for fill. They don’t hold any significant nutrients for your plants. But they will decompose over time and contribute later. Depending on the depth of your raised bed will determine how much of this material is necessary.

The second layer is brown dirt, clay, sand, and topsoil. Very little if any nutrients for your vegetables. This layer will support the layers above and give your raised bed the height it needs. Again, how much of these materials will be determined by the depth of the bed. Notice in the photo below the color of the dirt. It is brown. Our goal is rich black soil. Also, notice the depth of the raised bed. It is 24" deep. Our next layer will be the good stuff.

The third layer is a mix of compost, manure, peat moss, and garden soil. Mix these materials thoroughly as they all work together for the correct chemical balance. This layer is where your plants get the nutrients they need. 6 to 8 inches of these materials are at the top of your raised bed.

The fourth layer is the mulch. Mulch is made of decomposed wood products and help keep your soil cool, reduce weeds, and make your garden beds look uniform and attractive. Not putting mulch on after your plants are in will lead to problems down the road.

Second Layer - Clay Dirt, Sand etc...


Third Layer - Compost, Garden Soil, Manure, Peat Moss


The Dirt on 'Dirt'

Below is a breakdown of four crucial elements to building good soil for your raised bed garden.

Lawn Debris

Collecting lawn debris such as leaves, straw, grass clippings can be stored in a special type of bin (compost bin). They need to be turned every few weeks for the decomposition process.

While planning your garden projects, don't forget that this material will eventually become an amendment to add to your garden soil during the fall and winter. This gives time for the materials to decompose over several months.

The great thing about this method is that it’s free, and depending on how much you collect will determine if you need additional amendments.


This is the best organic material for your garden. Compost helps the soil absorb and retain nutrients and moisture. This is a continuous cycle in building great soil.

Many people prefer to purchase compost from a local garden center. This method comes in bags by the cubic foot, and it’s ideal for a small garden.

Another alternative is to have fresh compost delivered by the yard or more to your property. Depending on how much you purchase, it is recommended that a tarp is put over this for protection.


Manure is both fertilizer and a soil amendment. Manure slowly releases nutrients into the soil. Manure contains nitrogen, phosphorus, and potassium. Use composted cow manure during the winter months.


Mulch is used to retain moisture, help reduce weeds and keep the soil cool. It also makes the garden bed look attractive and uniform.

Good soil supports the plant but also anchors the roots. Good soil will provide the necessary nutrients, water, and air plants need.

Rich Black Soil


Avoid The Following Mistakes

Over the years I have learned a few things about gardening. The most crucial things were through the mistakes that I made. Here are a few for you to avoid.

Not enough soil in the bed - Make your raised beds deep enough for the plant roots to grow. In this instance more is better.

The wrong soil ingredients - Don't cut corners. Your vegetables need nutrients to grow well. They will tell you if you cheated them on nutrients. They just won't give you any veggies.

Improper watering techniques - Set up a good watering schedule for your plants. If you have the time invest in a drip hose watering system on a timer. You won't regret it.

Not enough sun - Your plants need 6 to 8 hours of full sun to grow. Planing in the shade will defeat your purpose for gardening.

Not planning ahead - Planning your garden projects is a must. Have a good Plan A and a better Plan B.

Planting the wrong vegetables - Learn about the vegetable you wish to grow. Knowledge is king and knowing which vegetables grow well next to another is very important. This is called companion planting.

What does pH level mean?

Soil pH is a measurement of how much acid and alkaline is in your soil. This measurement is rated on a scale from 0 to 14, with zero being the most acidic. On the higher end of the scale of 14 indicates the most alkaline. The number seven shows neutral. We want to strive for a pH level between 6.0 and 7.0.

Nitrogen (N) - promote strong leaf and stem growth and a dark green color. (Broccoli, greens, lettuce) Blood meal or Fish emulsion can be added to the soil for nitrogen.

Phosphorus (P) - promotes route and early plant growth, setting blossoms developing fruit. Important for cucumbers, peppers, squash, tomatoes. Adding bonemeal well help with phosphorus.

Potassium (K) - Promotes plant wrote bigger, disease, and stress resistance. Vital for carrots, radishes, turnips, onions. Add wood ashes or limestone.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2020 Reginald Thomas


Reginald Thomas (author) from Connecticut on December 04, 2020:

Thank you! You are entirely correct. I will add this point. Thanks again.

Peggy Woods from Houston, Texas on December 03, 2020:

One other tip I would add to making a successful raised garden bed. Put down a weed barrier before filling it with soil, compost, etc. My husband and I made a 3 foot high raised garden bed for my mother at one time and did not put a weed barrier at the bottom. Bermuda grass grew up through it and was a constant weeding problem.

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