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Wednesday, 29 April 2009

How Do You Classify A Garden?

Gardening in this new millennium, has become a very different creature to what it once was. In some ways this is an oddity - gardening as a craft being at its core, so basic and archaic, is so intrinsically separate from technology.
But technology has had its effect though - through the development and use of new materials and technologies but also through the spread of ideas via the internet and media.

A Plant Dominant Indigenous Garden

There is more discussion taking place today about gardening and about what defines a garden than has ever taken place before. This conversation is occurring between professionals and hobbyists, intellectuals and labourers.

Out of this conversation, a question I've been asking myself lately is -
'How do you classify a garden?'
Even as I write that, I can hear some people saying, "Why would you even want to classify a garden? A garden is something to be appreciated and felt, and admired."
That is all true, but I see so many types of gardens, from all over the world that it is becoming harder to fit them into the traditional definitions that I'm used to, and as a result, harder to understand.

I believe that people take comfort in our ability to divide and classify the world and put it into nice neat little boxes. In some ways it even makes us human - this ability to define something.

Gardening as an art-form, has not been spared this need to separate and define. Formal, Contemporary, English Country, Eastern, Natural, Wild, Indigenous, Zen...the list goes on and on.

A Structure Dominant Wild Garden

With this classification of gardens into types, and because of the continual segmentation, and the blurring of lines, I believe there exists a need to define gardens in more general terms.

To explain, I'll use an example that we as gardeners are familiar with - just as a particular plant has a Genus, and is then divided into its species, the Species of gardens (i.e. Tropical, Minimalist, Formal) need to be grouped together into Genera.

This is necessary, not for the sake of classifying for classifying's sake.
But rather as:
  • a way to clear up miscommunication between client and designer.
  • a tool for teaching and passing on knowledge in clear terms.
  • a spur to push designers and gardeners to try something different, and venture into new territory.
The most obvious way of defining, would be to look for the defining dominance in the design of the garden.
  • Plant dominant - Where the garden's essence is about the plants themselves (Tropical, Indigenous/native, English Country, Natural, Collector)
  • Concept dominant - These gardens revolve around an idea or concept(Zen, Feng Shui, Modern)
  • Structure dominant - These gardens have strong shape and/or geometry (Formal, Contemporary, Minimalist)
  • Function dominant - Where the function of the garden takes precedence (Lawn for playing, Parking Area, Patio)
This defining dominance would be primarily visual - it would be the character of the garden that unifies it or makes it stand out. It could also be intellectual - a garden built around an idea or concept that may or may not be immediately obvious, but that was the guiding principle behind its design. (e.g. Jenck's - Garden of Cosmic Speculation)

A Structure Dominant Formal Garden

But gardens are not always so easily put into their respective boxes, and here is where the Linnaeus analogy becomes inadequate. The gardens themselves may fall into more than one of the above groups. For example, a typical tropical garden at its essence is built around particular types of plants (Plant Dominant), but if the structure of the garden dominates, it could also be Structure Dominant. As to which is truly dominant would become a more subjective matter.

To use a more specific example - many of Gertrude Jekyll's garden's would have been strongly Plant dominant, but with Sir Edwin Lutyens' architectural input, they also had a very strong Structure dominance.

I see the practicalities of this idea being in creating a concept that makes communication clearer and simpler between client and designer, student and teacher, and between various professions relating to the gardening industry.

Gardening has been an art that has been nurtured by the hands of amateurs through the ages, and has at times, and in various cultures been analysed by the mind as well as the heart, but as the world gets internet-smaller, and communication happens across the globe, the thought processes behind garden design will and should become more apparent and utilised by the lay-person and professional alike.
For this reason, I believe that it would help if we spoke in similar terms.

Tuesday, 28 April 2009

Gardening on a Balcony

After 20 years of gardening, I'm amazed that I'm still amazed by the effect that plants have on a space. I don't often get to appreciate this first-hand, because I usually have to leave my gardens behind when I go home.

Michelle and I bought a flat a little over a year ago, and one of the things that really appealed to us was the big balcony, which in Durban is a great asset for enjoying our sweltering hot summers.
Its taken us a while, because up until now we've had other priorities, but we've finally gotten round to tackling the balcony.

The cage over the succulents is to keep our
vegetarian cat from munching

The catalyst was a pair of old pots that I had laying around from an old show that I did a few years back. After several coats of charcoal coloured paint to cover their awful green colour, and a quick trip down to the nursery, we had the impetus we needed to really get stuck in to planning and fixing up the area. Which up till now has become a bit of a dumping ground for all the stuff that has nowhere else to go.
A terracotta pot that we've tried quite unsuccessfully to grow herbs in, is now the home for all the succulents that I haven't been able to resist buying when I've been shopping for plants for clients.

Sitting down and appreciating the balcony with the plants, a cup of tea and Michelle's fresh baked biscuits this afternoon, it finally felt like a space that I can enjoy.

Now to figure out the furniture...

Friday, 24 April 2009

What does N:P:K stand for, and is it a four-letter word?

I'm asked this often, so here is the short answer:

N : Nitrogen (Good for growth of foliage)
P : Phosphorous (Good for roots and flowers)
K : Pottasium (Good for fruit & general health of the plant)
Four-letter word?: Yes & No

The numbers (e.g. 3:1:5 or 2:3:2) that you see on a bag of fertilizer represent the proportion of these 3 elements - N:P:K.

Some quick facts:
  • A lack of Nitrogen is usually quite apparent when the green foliage of your lawn or plants becomes pale. (Although this is not the only reason for pale leaves)
  • Phosphorous does not move through the soil, so it should only be added in small amounts near the roots of plants, so that it can be absorbed easily.
  • Potassium deficiency shows up when the edges of leaves and the area between the veins start to go yellow. Potassium helps plants handle changes in temperature.
  • Generally speaking, unless the fertiliser is slow release (it will have (SR) after the N:P:K) you should always water your plants straight after applying in order to prevent any burning of the plants, and to help them to absorb the nutrients easily. Wash your hands immediately for the same reason.
  • The plant family Fabaceae (e.g. Peas, Beans, Acacia, Indigofera, Crotalaria) has a symbiotic relationship with bacteria which actually helps add Nitrogen to the soil naturally.
But good-old-fashioned granular or chemical fertilizer is poo-pooed (sorry I couldn't resist that) in many circles these days, rather there is a strong move towards using organic fertilizers instead.

The problem with this particular type of fertilizer has resulted from its over-use, and mis-use. Chemical fertilizers are sometimes applied in larger quantities than can be absorbed by the plants or held by the soil, they then leach down into the groundwater and rivers, and can result in the death of fish amongst other things.
It is also believed that in large quantities over time, they can actually poison the soil and kill off the natural organisms that are essential for plants and organisms in the soil.

My personal opinion is that chemical fertilizers should always be just a very small portion of the food that we provide for our soil and plants. Because the elements are in their basic form, and therefore easily absorbed, they are often great as a short term solution.
But organic fertilizers, such as composts and manures, provide a whole host of other macro and micro nutrients, as well as improving the structure of the soil. For these reasons, they are always better in the long run.

Friday, 17 April 2009

Lazy Landscapers

Plants are to a garden designer what words are to a writer. The larger a writer's vocabulary, the better they are able to communicate with their audience.
Unfortunately many garden designers have a very limited 'vocabulary', and they tend to only plant those few plants that they know, regardless of the conditions or what might be appropriate to the site or design.

Every landscaper or garden designer does have their palette of plants that they prefer to use, but those preferences should never be at the expense of good design.

I have been seeing a profusion of 'landscapers' lately, that seem to have a very small range of plants that they use, with the result being that all their gardens start to look the same. In some cases I've had to fix some of these gardens that have been planted up with plants that are not suited to our coastal conditions. All this because garden designers are either lazy and/or have a very limited range.

I believe that the only justifiable excuse for getting stuck using the same old plants, is when we have to revert to plants that need to be easy to look after. In these cases, when the person caring for the garden has limited skills, then its defensible to stick to safe and easy plants. The challenge then for us as landscapers is to be looking for easy-maintenance plants that we can add to our repertoir for situations like these.

How can we as garden designers not be continually learning, reading, watching and testing. We should relish the chance to try new plants, and experiment with new combinations. We should be constantly stealing from others (with our eyes of course)!

But really, how can we justify always using the same old boring plants?

Friday, 10 April 2009

Green Roofing on a Massive Scale

I have written about the benefits of Green Roofs before, especially for us in South Africa, with our extremely warm climate. The insulation and resulting cooling effects that it would bring are huge. They can be beautiful at the same time as functional.

The Vancouver Convention Centre is an amazing example of what can be done.

Monday, 6 April 2009

Getting Control Back From The Aliens

Getting control of Alien vegetation is an important subject for any gardener in South Africa. Our water resources and indigenous plants are under threat, and we all need to learn to identify and remove invasive plants whenever we find them. Fortunately, we have a little help that reminds me a bit of the plot from The War of the Worlds.

The other day, while driving, I spotted a very unhappy Opuntia growing on the side of the road. It looked as if its life had literally been sucked out of it - and looking closer, it had!

Thousands of tiny bugs called Cochineal insects had latched on and were pushing their little beaks into the plant. They were quite rapidly killing the plant by sucking the sap out of it.
This way of dealing with weeds is called biological control, and South Africa is one of the top three countries in the world when it comes to this method of invasive plant control. Since 1914, we have introduced over 80 species of biological agents in order to control or destroy the invasive plants that thrive in our ideal conditions.

The concept behind biological control, is that because invasive plants are in a very strong position in a new environment with no natural enemies, the playing fields need to be levelled. The best way to do this is to introduce their natural enemies from their countries of origin. this either destroys, or helps manage the burgeoning alien populations.

Biological control is an ideal way to get rid of invasive weeds, because:
  1. it causes no pollution and affects only the targeted invasive plant
  2. it is self-sustaining and as a result, permanent
  3. it is very cost-effective
  4. it won't disturb the soil or create barren areas where other invaders could establish, because it kills the targeted plants over time, and allows the natural vegetation of the area to recover gradually in the shelter of the dying weeds.
Obviously these biological agents need to be introduced extremely carefully, and there are very strict controls in place to make sure that there are no unforeseen results. It doesn't work in all situations, but there has been excellent results with Water Lettuce, Port Jackson Acacia, Red Sesbania, and of course Opuntia.

Something else to think about, is that this little Cochineal insect can also be harvested to make a crimson dye which is sometimes used in food colouring. Try not to think of that next time you're eating food thats been dyed red!

Friday, 3 April 2009

Common Trees with Aggressive Roots

This is a problem I've touched on previously, but I'm amazed at how often people plant or leave trees with strong roots to do their damage. The initial title for this post was going to be: Warning: Trees With Evil Roots. But I can't really call them bad can I? These trees have amazing roots, and as a result they are usually very fast growing, are often able to shrug off many diseases and pests, and are able to withstand drought easily. So really, they are incredibly well-designed plants.

But the problem comes in when they are planted near drains, walls, paving, or in small gardens. The following trees are just the most common trees that I see mistakenly planted:
  1. Ficus (Fig tree)
  2. Erythrina (Coral tree)
  3. Cussonia (Cabbage Tree)
  4. Schefflera (Common Cabbage Tree)
  5. Caesalpinia ferrea (Leopard Tree)
These all have the tendency to damage pathways or drains if planted too near. A couple of restaurants in Durban (Manna Restaurant & Churchill's Coffee Shop) have planted groves of Leopard trees in their outside areas, and while they're great at the moment to sit under, they are doing huge damage to the drains below.

Leopard Trees - Soft and Aggressive

I also often see damage to walls by plants that expand outward, putting pressure on foundations and walls. They are planted when they are still small, but in time get much bigger than anticipated. Some of these are:
  1. Chrysalidocarpus lutescens (Bamboo Palm)
  2. Strelitzia reginae
  3. Many palms are planted while still small, but get much thicker.
Are there any plants that you've noticed in your part of the world that need warning labels?

Home Made Pest Control Solution(s)

I'm really not a big fan of pesticides or chemicals. Actually, that's putting it mildly...I hate pesticides. They are almost always ...