Raised Bed Gardening

Container gardening is fast becoming the standard method for gardening.  The time, energy and water requirements of planting in the ground are beyond the fast moving lives most of us live. The benefits of low maintenance, small space requirements, and great results fit lifestyles with little extra time and energy.  Container gardens can look many ways: pots, old wheelbarrows, old tractor tires,

 feed tubs, barrel halves, raised beds (permenant structures built up from the ground), and Earthboxes (the ultimate self-contained container system), just to name a few.  

Raised beds are especially popular for folks tired of managing a large garden but still want enough room to grow plenty of food.  Raised beds are also good for people who do not have adequate quality topsoil.  

Giant Cabbage in Raised at The Green House
(Red Walls-o-Water for Tub Tomatoes)

Raised beds were made popular by the book Square Foot Gardening which blasted many gardening myths on plant spacing and productivity.  In summary, the author demonstrated that plants grown close together yield more per square foot and provided the added benefits of reducing weeds and evaporation.  Using his 4x4 foot square, the author showed that a family of four could feed themselves with as little as 3 or 4 of these squares.

Are you ready to build your own raised bed?  If so, here are some easy steps to help you on your way to a successful raised bed garden.  And if you're more into container gardening, most of these steps are applicable to you as well.

1. Choosing the Location.  First, you need to know what you are going to grow.  Vegetables require full su

n.  Some plants do well in partial sun.  In Texas, "full sun" means that you can have some shade during the day and still have "full sun" (8-10 hours a day).  In early spring, be sure to take into account tree shade once the leaves have come out!  Drainage can also be important.  Do not build your garden in a drainage area and consider if how heavy rain runoff might affect your location.

2. Choosing the Size.  There is no best size or shape.  A popular size is 4 ft. by 4 ft. because you can reach all your plants without stepping into your bed causing compaction.  4 ft. by 8 ft. is also popular because so many bought materials come in 8 ft. lengths.  Heights of raised beds vary from 6 to 24 inches.  A minimum of 6 in. is needed to grow most plants.  Keep in mind that plants will make use of the soil below the raise bed as well.  Assuming that you are providing superior soil, the deeper the soil, the better your outcome.  Also, the taller the raised bed, the less stooping you will have to do.  Many beds will include a led

ge in which the gardener can sit upon. 

3. Choosing Materials.  If you are purchasing treated lumber and plan to eat what you grow, consider the possibility of chemical residue getting into your food. Avoid any materials that might contain contaminants that could enter your food.  

It can be fun (and less expensive) to think outside the box.  Recycle old lumber, garage doors, tractor tires, water troughs, etc.

4. Construction Considerations.  Be sure your container is strong enough to withstand the pressure of wet soil 

pressing against the sides.  Typically 2 inch thick lumber can span 4 ft. while 1 inch lumber should be supported every 2 feet.  Be sure to level the box.  Soil will shift and seeds will float away in unlevel beds make the bed somewhat unsightly.

Some experts say that all grass should be dug out before placing your container garden but we have used a double layer of cardboard along with a foot of soil to kill out the grass.  If gofers are a problem, tack some chicken wire on the bottom.  I prefer something looser than landscape fabric so the earthworms can travel back and forth!

5. Preparing the Soil.  Choosing the soil can be the most difficult decision of the project and it is the most important!  The quality of the soil defines your results.  Scraping up dirt from around the property may the be cheapest but it probably won't get you the results you are looking for.It will lack fertility and will most likely add weed seeds and possibly disease to your raised bed. Here are some easy steps to help you get started.

First, calculate the amount of soil you need.  Do this by multiplying the length by width by height.  Do this all in one measurement, e.g., feet.  A 4 by 4 ft. raised bed built to a height of 12 inches requires 16 cubit feet of soil (4 times 4 times 1 equals 16 cu. ft.).  

Main Ingredients: Compost, Peat Moss, Vermiculite, and Horse Manure

Next, choose your material.  You can use pre-mixed potting soil but this is usually the most expensive method.  You may also be able to purchase bulk "garden mix" or "container mix" from local composting or landscaping professionals.  Alternatively, you can make your own using inexpensive purchased ingredients, and optionally, materials around your property.

Here is an easy formula you can start with to create a "soil-less" soil which is lightweight, tilthy, and fertile. Mix 1/3 peat moss, 1/3 vermiculite, and 1/3 compost.  From there, you can add many different soil amendments to enhance your soil.  I have a custom "soil builder" which contains worm castings (9% nitrogen and earthworm eggs), corn meal (feeds beneficial fungi), dry molasses (sugars for beneficial microbes), humates (72 trace minerals), biozome (beneficial biologicals), and greensand (a mined mineral high in potassium and iron).  I also add several buckets of horse manure.  A 5 gallon bucket is approxim

ately .8 cu. ft.  Experiment and find what works for you. 

Remember, the SOIL is THE KEY to a successful garden, both in terms of yield, taste, and disease, pest, and drought resistance.

Once your soil is in place, mix and water thoroughly.  If you used a lot of peat, you may want to put a sprinkler on your bed because it takes time to get the stuff wet!  Stay tuned as we begin planting in 

our new raised bed....