If you want to grow the biggest, healthiest, fastest-growing vegetables or flowers, build yourself a raised garden. When you create a raised garden bed, everything is contained. You can fill it with all the very best soil, compost, mulch, and fertilizer.
Benefits
No matter what type of native soil you have, building raised garden beds allows you to introduce the perfect soil mix for whatever you want to grow without the need to alter the existing ground.
They are easy to moderate the soil's temperature, and this feature alone can increase the length of time you can grow for two reasons. First, they sit above the frost line, and therefore you do not need to wait for the ground to thaw. Second, a raised garden bed is a much smaller mass than the earth and can therefore be warmed quicker in the spring months.
Raised beds also help reduce weeds due to the selective nature of what you put in the beds and the ease of weeding access. You can also line the base of raised planters to protect from gophers and other pests.
You can control your drainage with more accuracy, depending on your requirements.
Size Guides
However, ultimately the key feature and benefit of a raised garden bed is their accessibility. No more bending over to ground level to treat your herbs, flowers, or vegetables.
Your raised garden bed should be no more than four feet wide for best accessibility and to avoid overreaching or stepping on the soil. However, if your garden bed is against a wall or fence and can only be accessed from one side, then a maximum of two to three feet wide is recommended.
Your raised bed does not have to be deep to reap all the benefits we have listed so far. A minimum of 8-10 inches is adequate. Although, ideally, vegetable beds should be at least 12–18 inches deep where possible.
Location
When choosing a location, you need to consider the requirements of the plants you are choosing. Whether they are vegetables, flowers, or herbs, different plants like different amounts of sun, shade, and shelter, it is also a good idea to choose a reasonably flat area to build your raised garden bed. Another location tip, particularly for a vegetable or herb bed, is to consider proximity to the kitchen.
Material considerations
There is almost no limit to the number of options available when deciding on a material to build a raised garden bed. Whether you are looking for something formal, something inexpensive, or if you are looking to use a recycled option, you are limited only by your imagination – with the following exceptions:
· Older cinder blocks can contain fly ash, which is the "cinders" that remain from burning coal and should be avoided if using for vegetable gardens.
· Railroad ties look great, but due to the way they were chemically treated can be considered potentially harmful to humans.
· Tires are known to contain heavy metals, and so are best avoided if using for food production, as the chemicals may leach into the surrounding soil.
· Pallets and treated lumber: There is debate around whether lumber treatment chemicals will leach into the ground. If you're not comfortable with treated lumber, you can staple polythene sheets around the interior walls as a barrier between the lumbar and soil. Just remember that adequate drainage is essential for a raised garden, so don't run the polythene sheet over the garden's bottom.
Preparation
Once you've decided what materials you will use to build your raised garden, its location, and what size it's going to be, mark it out. Then grab a spade, and skim off any grass and vegetation down about half an inch, which should get you down to bare dirt.
Spread about six layers of old newspaper or a layer of cardboard over the ground to help prevent weed growth, then wet down with a little water to hold the paper in place while adding soil.
The first layer should be green material such as green waste and some of the sod you removed when preparing the garden. This green material will rot down and provide excellent worm food, attracting worms to your garden and creating nice rich soil.
Then cover your green waste with layers of potting mix and compost, or make it even easier by simply filling with a prepared garden mix suitable for your intended garden.
The next step - planting out your garden with your chosen plants!
Hopefully, this guide to raised planter beds will inspire you and lead to many years of enjoyable gardening.