May 2017 -Making the Most of Your Yard (Part III)

Welcome to our May edition. Soon I will be saying welcome to our June edition and summer will be here. Hard to believe especially considering what a rainy spring we have had. In one sense it’s been great, we have needed the rain, however in another sense it’s so nice that we are past it. We know now what it must be like living in Washington state. And though this extra rain has been most needful we are still considered a Mediterranean climate and in designing/planning landscapes we must keep that in mind and avoid large areas of sod or water thirsty landscapes. Next year could be a dry year.  Wise stewardship of our natural resources should be everyone’s concern, for we all benefit when everyone cares. 

Now for our article. This is the concluding article for this landscape. Hopefully you have kept March and April’s articles to compare how the landscape has changed from installation (March’s article), to this last winter, six years later (April’s article) to the present. In review: the topics covered dealt with the process of coming up with a design that best fit the clients’ need (March’s article), to using plants to solve problems and a common design error (April’s article), to this month’s topics, plant selection and irrigation design. 

Let’s start with irrigation design. It will be hard to explain this with just words. Often, I will draw out the concept, making it much easier for the client to understand. However, let’s give it a go and see how good a writer I am. The basic irrigation design most installers follow is to put all the valves along the side of the house and then from each valve run PVC lines to their designated location, which in general is fine for average size yards. For larger yards though this is most inefficient and costly. Let me use the field of firefighting to clarify. Say we have multiple fires in a specific area. The procedure is to run multiple fire hoses, one to each fire from one fixed point, the fire truck or the engine as firefighters call it. The fires that are close would not need much hose, however the fires that are farther away will need much more hose and in that example, we have a problem called pressure drop. Being that my son in law is a fireman I conferred with him to make sure that what I assumed happens, truly does occur. On the fire truck the water pressure is increased for the hoses that travel the farthest so that the amount of water that comes out is sufficient to put out the fire. In irrigation we account for pressure drop in long runs by starting out with larger diameter pipe then every so many feet we scale down the size of the PVC to maintain the pressure. Since the pressure from the city is fixed we cannot increase the flow, however by scaling down the size of the pipe we “massage” the pressure to keep the loss at a minimal. Therefore running from one fixed point to multiple points in the yard requires a lot of PVC pipe, or using our example, a lot of fire hoses. And as just mentioned we need multiple sizes at specific lengths. It can be a hassle keeping the sizes and amounts per valve in order and many trenches later the job is finally done.   

However, and again using the field of fire fighting, what if instead of running PVC all over the yard we instead place fire hydrants at specific points in the yard and run our PVC from there? You would use a lot less pipe and they could all be the same size for the distances would be short in comparison and far fewer trenches would need to be dug. In landscape terms a fire hydrant is a main line, a pressured line that always has water in it.  The valves would then cover specific areas or regions in the yard. Being centrally located within a 40- foot radius (assuming we are talking about sprinklers, not drip) each valve would need to water 20 feet to the left and 20 feet to the right, easy. Following this model we would have groupings of valves and we would  have used less PVC, less fittings, and  less labor  and maintained strong water pressure. The one thing we would use more of is the irrigation wire but in comparison to the other costs the wire is cheap.

This yard has three valve locations, three valves per location.  In a nutshell then this is a brief overview of  irrigation 101 for big yards. For average yards the normal way of doing the irrigation is generally fine, however we also install different than most. To explain that I would not have space to discuss plants. The extra steps we take in average yards adds more time (cost), but it is a stronger system, whereas with the large yards it takes less time and saves money, just the opposite. 

Now for plants. Because of my background of growing plants, plants are my passion. I love creation and anxiously look forward to each spring to see  the new varieties that the breeders have created, like the new model cars that come out each year. The size of this yard allowed me to use a multiple plant pallet without it looking too busy, something I would not do in an average size yard. We have about 50 different varieties of plant species including the trees. That is a lot, yet it works for big yards and is the key to having color throughout the seasons, with multiple perennials in bloom within the same season. There is so much to planning companion plants, but to simplify it we have three major groupings: true semi-drought tolerant plants that once established need deep but infrequent watering, your average plants that need scheduled watering and your bog plants that love moist soil. This later group is great to use in shady areas or at the base of slopes, since all the water travels downward. To group plants correctly takes some study, but it is not impossible either.  

For this month, I am going to forego our garden section to share the following. I am considering teaching classes on landscape and the care needed afterwards. The timing of these classes would be from November to mid-February. The format would be very similar to the articles but more in depth and more detail. If this is something you would be interested in, please send an interest email to Amber’s email and depending upon the interest level we will move forward. Thank you.