Welcome to our June edition, and our continued discussion on the Mediterranean Theme. In May we addressed some of the construction concerns we had with this project, as well as the concerns of the client. Access, a commonly shared concern for all sloped landscapes, and the phase of the project that represents the greatest effort, was achieved by using stone treads as steps and pressure treated wood with 2” galvanized posts as the retaining wall, which in turn framed out the walk. For more discussion of this phase, please see last month’s article under publications on my website (or Home Improvement’s website).
To appreciate the work and effort which I just summarized, the time it took to add the two sets of the main access steps, the three set of steps located on the upper tier, plus the retaining wall and walk is the equivalent of three men for 10 days. Had we used block, as we do on bigger slopes, it would have easily taken a week longer. The hill was only a part of this landscaping job. The total time spent on the hill alone was a month, so half of our labor was just in the construction phase. Once this phase was completed, we continued with irrigation, drainage, plant selection, night lights and bark. However, all these phases have to be considered during and prior to completing the construction phase.
How did we plan for them? Good question. For irrigation, drainage and electrical we add “sleeves” (hard pipe that goes under the steps or walkways) that later we can connect to and continue. In theory, this prevents us from having to re-do -completed work. However sometimes as the project advances, the homeowner modifies it, or at times while trenching we run into lava cap (no surprise when dealing with a slope), requiring us to re- think our sleeve locations, and redo portions of the work. These are all the “joys” of working; we all experience this.
The other aspects of drainage, PVC, and lighting can be done in sequence with construction. Planning drainage for a slope is easy. Since all water goes to the base of a slope, a drain line needs to be added there to redirect the water away from any plants or hardscape. In the job pictured, that happens to be a pool. With irrigation, the goal is always to get the right amount of water to each plant. With slopes, however, run-off is a concern. We want to minimize the water running down the hill, yet get good penetration around the plant, so drip irrigation is preferred. This property had impact sprinklers, which are essentially useless on such a steep slope. Especially as the landscape grows, the plants closest to the sprinklers tend to block the irrigation from getting to the rest of the plants, causing even more stress and die-back on the plants.
In running drip, we install “stubs ups,” pvc line that rises up at specific points to which we connect drip line to, once the plants are in. Upon completion of this phase, it’s “show time.” It’s time for the plants, the heroes of the landscape. Aside from watching the plants mature over the years, the planting phase is my favorite part of the job. I feel like Adam at times, gardening/designing with the beauty God has created in the plants. It’s one of the perks of my job!
Selecting plants for a sloped landscape is somewhat critical. Not all plants will thrive on a slope. And as is typical of most slopes, the soil is not the greatest; it is often filled with cobble, and/or lava cap (as noted), which minimizes the amount of actual soil. Therefore sloped landscapes require plants that are adaptive to such conditions, and have strong roots. Natives are good choices (except at the base of a slope, where it tends to be wetter than natives like), but an all native landscape can be “rough looking,” especially if landscaping around a pool where a more refined look is desirable. Fortunately for this landscape, the soil in Elk Grove is quite good; unlike that of Folsom, El Dorado, or parts of Roseville, Rocklin and Lincoln, where cobble can be at least 40% of the soil content.
Understanding the soil conditions is only part of the plant selection equation. You must also understand the plants themselves. Within your chosen theme, which plants will best adapt to a slope? Also some themes, such as the Tropical theme, are not given to “tough plants,” therefore the theme should be blended with a heartier theme like Mediterranean or Northern California. This is where the working plant knowledge of the landscaper plays a critical role. It is not too difficult to make a landscape look good right when it’s finished, especially if it was just dirt or overgrown plants before. But how will it look a year from now, two years, or three? Will the landscape thrive, or will it decline over the years? I am very grateful for my fifteen years in the wholesale nursery business that exposed me to a multitude of plants, and now allows me to adapt the plant selection not only according to the theme, but to the terrain as well.
As for bark, there is nothing better than shredded Redwood or Cedar, sometimes called “Gorilla hair.” It is nasty to work with, gets into your shirt, socks etc. but once it has been wet down, especially after several rains, nothing holds better. And night lights, as with plant selection, well … that’s an “in house secret,” but a properly lighted slope is beautiful, giving it an almost mystical dimension and beauty. Until next time,“Good Gardening”
A very common plant, and often incorrectly used, is Lavender or Lavendula (its botanical name). Native to the Mediterranean region (mountains of Southern Europe) it is known for its fragrance, used for its medicinal qualities of relaxation and healing, and is found in soaps, facial creams and teas. The new flowers can be cut and dried and used in sachets and/or potpourri. With respect to its landscape qualities, it acts like a native requiring little care, but it does require good drainage. Because of its habit of spreading, and rooting as it spreads, it is a perfect candidate for sloped landscapes. There are many species, each with their distinct qualities. The English Lavenders are smaller in size (2’ by 2’), Spanish Lavenders are the medium growers (1 ½’ to 3’ height and width) and the French lavenders are the largest (approx. 4 ½’ by 4 ½’). Western Garden Book does a great job in breaking down the varieties within each of the three species, and there are more specie types that have been crossbred with the three listed, creating new variety types. Viewed in the picture is ‘Munstead,’ an English type Lavender. The most fragrant of all is a cross breed Lavender, called L.x intermedia ‘Grosso,’ a midrange grower, widely grown in France and Italy for its fragrance and oil, and makes a great flower for drying. Blessings.