by Philip Fry
One of the main differences between colonial and habitat gardening is the approach taken to the ecological process of natural succession, the complex sequence through which plant and animal populations replace each other on a given site. With geographic and climatic conditions remaining more or less stable, the process of succession is initiated following a serious disturbance to a site and works towards a state of relatively self-sustaining equilibrium. Succession is about what happens in a given place over a period of time; the location, size, neighbourhood, and the living conditions on the site all have an impact on the process of habitat transformation.
The nature of the disturbance at the origin of a succession sequence has an influence on the process. Disturbances are of many kinds – lightning striking in a climax forest, a bulldozer “improving” drainage along a stream, a beaver dam which floods a valley, clear-cutting followed by burning, repeated over-grazing of livestock, preparing the infrastructure for a housing development.
In general, though, two main types can be distinguished: primary, in which the disturbance is so thorough (such as clearing a forest area and grading the resultant field) that little of the site’s past remains; and secondary, in which the disturbance, even though it might be severe, does not completely “wipe out” the past of the site. In this type of site, regeneration frequently takes place at the same time that “colonizing” species appear with or without human help.
What distinguishes the main European garden traditions (the source of our colonial gardens) from habitat gardens is the degree and manner in which natural succession is espoused as a gardening principle. The European approach tends to exclude succession to impose a preconceived mental and aesthetic order on the site, and often treats soil and plants as mere materials in the attainment of that goal. The extreme example of this tendency is the French formal garden as seen in the work of Le Notre. In contrast to this, habitat gardening is a constantly renewed attempt to understand the processes of succession taking place on a site and to collaborate as best possible with what is happening. Lawns and golf courses for example, are historical relicts of European landscaping traditions that, while trying to be immutable in their perfection, have a negative effect on biodiversity; a butterfly meadow is in constant change and promotes biodiversity. The practical and aesthetic goal of habitat gardening (and its larger scale version, landscape restoration,) is not to create a particular “look” or “style” reminiscent of a lost past, but to ensure the over-all ecological health of a site. Instead of trying to fashion a beautiful thing, habitat gardening attempts to set up natural processes so that, as a correlative of ecological health, beauty just happens.
The difference between European garden traditions and habitat gardening is about general outlooks and degrees of application. In this sense, the principles of habitat gardening are far from new. In the 1730’s, the poet Alexander Pope wrote the following lines in his “Epistle IV, to Richard Boyle, Earl of Burlington (I edit for brevity):
To build, to plant, whatever you intend,
To rear the column, or the arch to bend,
To swell the terrace, or sink the grot;
In all, let nature never be forgot…
…Consult the genius of the place in all;
That tells the waters or to rise, or fall;
Or helps the ambitious hill the heav’ns to scale,
Or scoops in circling theatres the vale;
Calls in the country, catches op’ning glades,
Joins willing woods, and varies shades from shades;
Now breaks, or now directs, th’ intending lines;
Paints as you plant, and, as you work, designs…
…Spontaneous beauties all around advance,
Start ev’n from difficulty, strike from chance;
Nature shall join you; time shall make it grow
A work to wonder at perhaps a Stowe.
To overcome the effects of climate change and loss of biodiversity, “consulting the genius of the place” would seem to be a wise beginning. In my next column, I will discuss various applications of the principle of succession in gardening. If you wish, contact me at [email protected].