Raised Garden Bed Construction
Enjoy Gardening More, Off the Ground

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All you have to do is pick the location, set up the retainer walls, and fill your garden bed with a good soil and compost mixture, seed and/or plant, and then mulch around the plants.

More and more gardeners are using raised beds because they give a head start each year.

Since the bed is above ground, the soil warms to good growing temperatures earlier in the season.

That means an earlier, and a longer, growing season.

If you like cool weather crops like peas and broccoli, raised beds are a great way to get more of your favorites onto your plate sooner.

Decisions To Make

First, decide on the height you want the bed, and whether you want a tiered garden (multiple levels).

If anyone who is disabled will be gardening, take this into account as well. Someone in a wheelchair will want to garden at chair height. Someone who can't bend over may be able to sit 12 inches off the ground.

The above considerations will help determine what material you use to build it.

Now it's time to pick out the type of material to use for the walls of the raised garden. There's a broad assortment of materials that you can use for the walls.

You can use rocks, which will give the bed a "farmy" sort of look. The rocks also absorb heat during the day, which can help warm up the soil early in the season.

Bricks or blocks will give a neat and tidy, almost formal. Wood is the most commonly used material because of price and ease of assembly. Some people use slab wood (the first cuts off of logs, with one rounded edge) since it's cheaper than lumber.

Some people use railroad ties because they're cheap. We urge you not to use them due to the creosote that used to make them. The creosote can leach into your gardens.

And do not use pressure-treated wood. The chemicals used to treat the wood can leach into the bed's soil. If you have small children, you definitely do not want to use pressure-treated lumber.

Whatever you use to build your garden with just get enough to make it as high as is convenient. Determining the height of the bed is up to you, but, as discussed above, consider what height the gardeners want to or can bend down to.

Most raised bed gardens are 1 to 2 feet tall. Some are even 4 to 5 feet tall. You can even create a tiered garden at different levels. What you do is dependent on your budget and the effort you can put into this project.

If you live in a cold climate, a few extras can allow you to build a mini-greenhouse, or a cold frame. For a greenhouse, stick lengths of iron rebar into the bed at the corners and along the lengths.

When it comes time to make the greenhouse, take lengths of plastic tubing and fit them over the rebar. This results in a curved surface. Lay clear plastic over that surface and attach it to the tubing.

If you have old storm windows, you can make your bed to fit the windows. Then place them over the bed in spring when you've planted seedlings, creating a cold frame for them.

Next, determine where to put your raised garden beds. Some points to consider:

• the amount of growing area needed
• the amount of sunshine needed for the plants you'll be growing
• the amount of sunshine available (you should have at least 6-8 hours of direct sunlight on the beds)

If you'll be building a raised garden bed next to a building (e.g., the south wall of a shed), you probably won't want it much wider than 3 feet, so that you can reach the back of the bed with straining your back.

If you plan to build a free-standing bed, you can go as wide as 4 feet. This means that the farthest you'll have to reach is 2 feet from either side of the bed.

Building the Raised Garden

Before you build the bed, remove the topsoil from the building site. Set it aside on a sheet of plastic or cardboard. You'll be returning it to the constructed bed when you're finished.

Once you've built your bed in whatever design you've selected (shaped, tiered, or a simple square or rectangle), it's time to fill it with a soil/compost mixture. If your bed is a foot or so high, mix compost in with the topsoil you removed earlier and fill the bed.

If you've built a bed that's 3 or 4 feet high, you'll need a lot of soil and compost. You may want to place some large rocks in first, to ensure good water drainage and to reduce the amount of growing medium needed.

Add the soil/compost mix to within two or three inches of the top of the bed. You may need to add more over the next few days, after the mix settles in the bed (especially if you've added rocks to the bottom). So keep some on hand to top up the low spots.

Planting the Raised Garden

At last, it's time to plant. You can sow seeds directly, place starter seedlings, or put in more mature plants.

As soon as you have the plants in the new garden, mulch them so that they don't dry out. I call mulch "mother nature's blanket" because of its protective qualities.

Water when needed, which may be more often that usual due to the extra sun the bed will receive.

Take pride in what you built, and enjoy the fruits of your labors, literally!