Part one: Trex® and the raised garden bed

Recycled plastic and wood board

This recycled form of compressed plastic and wood handles heat, cold, wet and other weather conditions without damage.

Raised bed gardening has become popular, and rightly so. By building elevated garden beds you can avoid dealing with imperfect local soil, help protect your plants from invading pests (and even your over-enthusiastic pets), and allow you to concentrate water and plant food where it is most needed. Raised beds are helpful for the handicapped and, because they relieve much of the bending and stress of ground-level gardening, can keep the rest of us from injuring ourselves, too

One problem with building raised garden beds can be the toll that outdoor weather can take on the container materials. Wood can rot or be invaded by termites. Cedar and redwood are the two most commonly resistant woods, but they eventually break down too, and still need regular applications of oil, paint or waterproofing. Treated wood like railroad ties and possibly ‘green wood’ can potentially leach chemicals into the soil so should be used with caution, especially around edibles. Vinyl can be a good solution but may be too flimsy for most uses unless it has a hard core added. Stone is another good choice, but needs to be lined or sealed so water and soil don’t filter out. Cement blocks can work well, but they can harbor pests in the holes, add lime to the soil and may not look very attractive. One more alternative as a building material is to use Trex®

Trex® is not the least expensive of materials since it is fabricated and requires more money to produce than something that is simply ‘harvested’. But it is made from recycled wood and plastic that would otherwise be filling up our landfills. It also is highly durable so the initial expense will be recouped in the first few years by savings in labor, repair, preservation treatments and overall maintenance. It makes an excellent material to build low maintenance raised garden beds.

One historical note about the company which carries the name of its product, Trex, is that it was formed as a division of the oil giant, Mobil Corporation. Organic chemist Roger Wittenberg independently discovered that compressing shredded waste plastic with sawdust could produce a superior building material. Mobil, being the country’s biggest producer of disposable plastic products was attracted to Wittenberg’s concept and worked up the timber application which was called Timbrex, later shortened to Trex®.

Using Trex® is Eco-friendly saving non-renewable or slow-growing resources and helping to reclaim waste. For the homeowner, using it will require little maintenance since it doesn’t need to be painted – ever – and will not split, warp or rot. On the downside, it is more costly than wood, but will make up the difference over time with its lack of care. It is also heavier than wood, and it is not structural. It was formulated for walking surfaces, railings and trim rather than for supporting beams. This means that if lengths are too long on the sides of your raised garden bed and lack enough supporting posts, they may curve or bulge slightly.

Use Trex® for a long-lasting, easy care material that is safe for using in vegetable gardens and for use with children and even mouthy pets. Unlike other materials that will require painting, washing, replacement and other maintenance, once your garden is built you can focus on growing your plants rather than caring for the container.

Check out the second part of this article, Part Two: How to build a Trex® raised garden bed, for directions on constructing the elevated garden.

Raised planter ready to be filled with soil.

How to build a Trex raised garden: the posts have been cut and filled with concrete, the bottom lined and this planter is ready to be filled with planting soil.