Are raised beds worth the effort and expense? The simple answer is yes, and here are a few reasons to make room in your landscape:
• Raised beds give the gardener an opportunity to control key factors such as soil make up, drainage and sun exposure.
• No foot traffic through your raised beds means less compacted soil.
• Plants thrive when their roots can travel freely.
• A bed that is raised even a foot can avoid many of our region’s pesky weeds. When the bed is fallow, a barrier of newspaper or plastic can add extra weed prevention.
• A raised bed constructed at seat level can reduce the amount of stretching needed to tend it.
• Heat gain that a raised bed receives provides a longer growing season; visqueen or glass extends the season.

Raised beds come in many forms, with a wide range of cost and materials:
• Mounding of garden soil can outperform a traditional ground level planting area.
• A rockery or a stacked stone wall can be inexpensive and attractive if built well, but maintenance can be an issue. Rough rocks are not usually comfortable seats.
• Segmented rock walls can be a more expensive, with a range of sizes and colors, and involve straightforward installation. Capped walls can be very comfortable seats.
• Cedar raised beds are very common. Cedar is naturally decay and insect resistant and readily available.
• Pressure treated lumber can be used for raised bed walls. Even though treated wood will have a long life, its use around raised vegetable beds is controversial due to the possibility of chemical leeching into the soil and vegetables. (My raised beds are pressure treated 2 x 8’s that were once deck joists. When constructing my beds, I lined the inside of the walls with a resilient plastic liner, protecting my food (and me) from any unwanted leeched chemicals.)
• Poured concrete raised beds are an expensive but very long lasting option.
• Other materials that have been used to form raised beds include concrete board (Hardie Plank), plastic/composite lumber (Trex, TimberTech, Monarch), and formed steel. Winter is the season that few think about landscaping and gardening but it is a great time to prepare for spring. A raised bed that is installed early has time for composting and other important soil building amendments. Put the effort in now, avoid the rush of building, planning and planting all at once. Leave a little time to contemplate and reflect, how does one prepare parsnips? Bok choi?

Zach

I recently read an article in the September 2009 Landscape Architecture Magazine ‘Haag’s Edible Estate’.  For those of you who don’t know, Rich Haag founded the Landscape Architecture program at the University of Washington and has designed some very notable places including Gasworks Park here in Seattle and the Bloedel Reserve on Bainbridge Island.  This article looks at the landscape of his private residence in Capitol Hill, which is an active experiment and example of what he has coined ‘nutrimental horticulture’.  The term is a mouthful but the ideas behind it caught my attention immediately.

Balancing the utility of a food producing garden with a landscape that is also beautiful and welcoming is something that drives many of my designs, including my own gardens.  Gardens are about discovery and activating our many senses.  Showy flowers and an intoxicating smell are great but think of discovering your first ripe strawberry; this evokes a special reaction.  Why can’t all landscapes have this multi-sensorial experience? They can.

One plant that is very easy to utilize in a landscape are blueberries. They are tolerant of a wide range of soil and light conditions (err on the side of shady and moist) and beyond the berries, the leaves have great fall color, changing to a bright red as the plant goes dormant.

If you are looking to create an informal screen, try red raspberries.  They grow into 5-6′ canes which spread through rhizomes over time.  Raspberries can be perfect for obscuring a utility shed or a tall cedar fence.  Many varieties of raspberry will produce fruit multiple times throughout the summer.

Does your garden need a bulletproof ground cover?   Similar to the aforementioned strawberry plant (which is a must) creeping bramble (Rubus pentalobus) sprawls low to the ground and produces bright orange, raspberry-like fruit.

A great way to bring structure to the garden is a trellis.  Trellises allow plants, especially vines, to grow vertically and often with a dramatic result.  They can support garden variety vegetables like climbing beans and peas that can be grown throughout the year.  As an alternative try grape vines or better yet, hops.  This summer I grew hops (Cascade variety) for the first time. They quickly grew to about ten feet tall with pendulous clusters of yellow green hops, a surprisingly good turnout for the first year.  Hop plants grow from rhizomes that mature and increase in size over time producing more and more hops.

Lastly, an edible plant that makes both an architectural statement and is very sought after for its culinary uses, the artichoke.  This plant may not be for everyone but it is dramatic as a focal plant. Mature plants can grow to be 6-7′ feet tall with bold serrated fronds and large thistle flowers (the artichoke).  Tall and conspicuous, I see it as the Palm Tree of the garden.  Unlike the Palm, however, the artichoke is perennial and will die back in the fall to emerge in spring.

I will readily admit that I have had mixed results with some of these plants (especially the artichoke). To me the experiment is a part of the experience.  Try new things alongside successes of the past.  It is a great way to discover what works in your garden landscape.

Zach