An Ecological Approach to Interiorscape in the 21st Century

Pests are a symptom; they are not the root or the cause of plant decline.

As any experienced plant professional will attest, sustainability is our mantra; we go to great lengths to acquire an account and to maintain and retain it. Why then would we not use every tool at our disposal to ensure we achieve that end? As I have stated previously, often times innovation does not arise as a novel creation; rather, it can emerge from an old technique or process seen in a new light or from a different perspective.

Simply put, biophilic design is designing in natures image. What better system to emulate than nature herself? The building blocks of life are quite literally star dust. It was not until the emergence and proliferation of autotrophs that the cornucopia of life on earth became manifest. It is a little-known fact among the general population that the fossil fuels we use so liberally today accumulated as a result of the absence of rapid decay. White rot fungi did not exist until relatively recently (geologically speaking) and it was the absence of these critters that allowed truly massive levels of autotroph detritus to accumulate, become buried and to be transmuted into hydrocarbon ooze, the basis our our modern and complex civilization. Fungi are, quite literally, responsible for loosing the chains of biological entropy on earth.

Statistically speaking, the top six inches of a soil harbour the bulk of the population of micro flora and fauna that fuel primary productivity on earth, this soil complex, organic and inorganic, can be translated to 2 million pound per acre. It is here, in this mysterious and magical colloid, that the building blocks of life are present in forms available to autotrophs – plants and the vegetation they create. These denizens and the vegetation they support have evolved over hundreds of millions of years. Contemporary plant science, as it is most commonly practiced, would have us believe that a healthy and productive plant or vegetation sequence can be appropriately cultured with a handful of nutrient inputs:  the holy trinity NPK, and a suite of perhaps 15 micro nutrient associates. This misunderstanding is responsible for most, if not all, of the negative plant propagation and production outcomes we face. The interiorscape environment differs from traditional horticulture and agriculture in many ways, not the least of which is the limitations that interior environments present with regard to refortifying the soil medium.

What would you say if I told you that an instrument was available that could be used by anyone in the field and that it could quickly and precisely inform you that something is not right with your soil, that you are likely to be presented with increasing and costly pest pressure, that your soil structure is lacking one or another vital component, that your nutrient levels are askew, your light levels are sub optimal, and that it could reduce your pest scouting and treatment costs, reduce replacement costs, increase your margin, facilitate happier and more successful and productive technicians, lead to increased client retention and satisfaction and grow your brand? Would you call the cookie truck? Laugh, roll your eyes, ask me where I buy my tin foil hats? All valid rebuttals if you don’t have an open mind – which you should have – remember you are a foot soldier tasked with growing our vital industry.

A refractometer is the instrument I am referring to. Its present form is an adaptation of the Hydrometer invented by professor Adolf Ferdinand Wenceslaus Brix, 19th Century German chemist (1798-1890); he was the first to measure the density of plant “juices”. The unit degree Brix (Bx), a measure of specific gravity is named after him. The science of wine fermentation and alcohol production will forever be in his debt. It was not until the 1960’s when the Floridian agricultural scientist Carey Reams began utilizing Brix in agricultural production with the use of refractometry that the full potential of the technique became manifest. He created an index, presented it to ACRES USA in the early 1970’s and agriculture has never been the same.

What exactly are plant juices?

They are:

  1. dissolved minerals (salts, acids, alkali)
  2. carbohydrates (simple sugars)
  3. amino acids (proteins)
  4. lipids (special case: oil & water don’t mix; form thin films)
  5. almost any molecule with covalent bonding
  6. very large suspended particles (colloids)

Why are these substances vital to plant nutrition?

Plants have evolved over geologic time, mechanisms that exist provide for proper functioning, anything less leads to stress. Plants under stress are easily identifiable to pests and they will exploit that stress. A modern adage comes to mind “if you build it, they will come” Healthy plants, those with the right “juice ratio” are unpalatable to pests and if they do begin to feed they will very shortly succumb and actually die. A healthy plant also feeds the soil biome, each night with the dying of the light, plants begin to trans duct sap to their roots, these substances feed the bacteria present in a balanced soil, these critters in turn feed the beneficial metazoans and create a rhizosphere virtually immune to infection.

What we want to create is a positive feedback loop. How, you may ask, do we do that? It begins with a healthy soil. Modern propagation techniques are designed for rapid turnover, if you have ever been to a large and successful facility, every square inch is utilized on an ongoing basis. Efficiency in production is the key and sadly this does not usually translate to best practices with regard to down stream uses. Most propagation mediums are not really soil but rather incomplete synthetic representations of soil. We can correct for this shortcoming with some rather modest inputs: as one who has handled millions of plants I speak from experience, in almost all cases there is room in a container for a little scraping, removal, and the addition of a top dressing. An ecological top dressing is really an inoculation, I recommend a bit of biochar, a bit of glacial soil or similar product, a bit of humic material (solid or with first watering in liquid form) and the removal of some of the lower leaves. The latter recommendation is not a transient thought but rather an evidence based cultural technique that I will address in a future blog dealing with the reality of creating a micro environment conducive to facilitating the process of toxin removal for indoor environments.

When should you use a refractometer?

At the beginning, during, and at the end of any plant installation cycle. Firstly, a representative sample should be removed from each new plant shipment and examined, the result should be recorded; secondly, during the maintenance cycle, you decide when and where based on observation, extent, and differences in each interiorscape; thirdly, at replacement. In each instance, you have to record the results. An acceptable reading of Brix is 12 degrees or higher, a lower reading is indicative of stress, your skill and experience will be required to ascertain the nature of the stress. Preparation is the key to success; it begins with a balanced soil. Maintenance is next; refrain from the use of chemical food, many organic alternatives exist and they will feed your soil as well as your plant. If you buy in and practice evidence based ecological alternatives you will not require pesticides which in almost all cases simply launch you onto a well-known treadmill, one that begins and ends in costs, financial, intellectual and ultimately reputation.

Chris is a plant biologist and forester who has dedicated over two decades to plant ecology research in addition to acquiring almost 20 years of experience in the garden center and florist sector. He graduated from Trent University with an Honours degree in plant biology and from Sir Sandford Flemming College with a diploma in Forestry. As an ecologist, Chris has been involved in many projects, large and small, from government directed natural resource management audits and climate change research with carbon sequestration in permafrost peatlands to natural vegetation restoration following disturbance. As an garden center and florist business owner in the Lower Mainland of British Columbia, he has born witness to the tremendous change that has occurred in the horticulture industry over the past twenty years.

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  • the Ficus Wrangler

    Super article Chris. Do you know if there is anyone in the industry using a refractometer today?

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