Naturalizing your city backyard - A visit with Henry Kock
by Walter Muma
This past May (1999) I had the opportunity to visit
Henry Kock's house in Guelph, Ontario. Henry is a horticulturist at the University of
When Henry purchased his house 6 years ago, both his front and back
yards were 100% lawn, except for a row of trees along the property line.
He sat out back by the rear of the house, and thought about what he was
going to do with his new property. At first, he thought about doing what others expected
him to do with it, given that he was a horticulturist. That is, to create a manicured
formal garden. However, this soon gave way to him thinking that he should instead do what
he himself wanted to do with it. Inspired by ideas gleaned from the Gosling Wildlife Gardens at The Arboretum of the
University of Guelph in Ontario, he decided to naturalize his entire property.
From that beginning 6 years ago, Henry was worked what seems to be a
miracle. It is now home to over 400 species of plants, all of them native except for a
handful. In the area of a typical urban backyard he has created diverse mini-ecosystems of
prairie, forest, rocky area, pond, marsh, bog and meadow. One could easily spend an hour
wandering around looking at all of the variety and beauty that is there.
Converting hundreds of square feet of lawn to forest and field is an
enormous task. So
how did he do it? In the remainder of this article I share some of
the processes that Henry went through, as well as tips he gave on doing a similar thing
The first principle to go by, Henry says, is to just sit and let the
land speak to you. Make yourself comfortable in your own yard and create the privacy that
you desire. Henry's philosophy is that the essence of the landscape should be one of
creating "rooms in the garden" (not unlike clearings or "rooms" in
nature). He started with a cedar rail screen near his back door to create some privacy
from the surrounding houses. This was made from a set of cedar rails stuck vertically in
the ground, with old bicycle frames attached to them to satisfy the artist in him.
These screens and walls also help to define space and create the
illusion that the place is quite a bit larger than it really is. He has continued to add
natural and "found materials" sculptures to the yard over the years.
Surprisingly, these actually add to the beauty of the area rather than, as you might
think, looking like "junk". There are also a number of rotting stumps and logs.
These both look picturesque as well as providing habitat for insects and fungus.
As for what to put into these "rooms", observe the plants in
your region and listen to them and let them tell you where they should go and what you
should be doing.
The next challenge was to reproduce the necessary conditions to create
each mini-ecosystem in his backyard. Henry says that the best way to learn how to
accomplish this is to go out and look at a wild area and then emulate it in your own yard.
Examine what plants grow there, whether they are in the sun or shade, what type of soil
they're in (sand, loam, gravel, clay; wet vs. dry) and what type of debris is on the
ground (leaves, small branches). Generally, plants are very hardy and they will grow in
many varied environments. They don't have to be located in their absolute ideal
Don't be afraid to move plants around if you find that you have put
them in the wrong place, or your plans change. Just make sure that you transplant enough
of the roots for the plant to stay alive and healthy.
Henry doesn't water his plants except for the initial time period after
transplanting them. He figures that if they can't survive under the usual weather
conditions of the area, then they don't belong there and should be relocated or allowed to
When doing a project of this sort, one of the keys to hassle-free success is
good neighbour relations. Henry advises that you start your naturalisation project slowly.
Invite the neighbours over and show them and explain to them what you are doing and why.
If they like a particular plant, the next time that you thin that plant out or transplant
it, offer them some of it for their own garden. Get them interested in what you're doing.
Show them that it's not threatening.
Leave some mown grass areas, so that people will still think that
you're at least partly "normal". Grassy trails through your yard will wear
better anyways. One of the biggest fears that neighbours will have is "weeds",
especially dandelions. When you show them around, show them that the only places that
dandelions are growing are in the grassy areas!
Be sure to convey the (correct) impression that you're not just being
"lazy" and just "letting it go" to weeds. Show them the various plant
species, that they are native plants and therefore belong here, and that you are doing a
lot of work to recreate particular environments.
Obtain plants from nurseries, friends, native plant sales, or areas
slated for development. Collect and sow seeds. "Plant rescues", where plants are
transplanted from areas slated for development, are also a good source since the
plants will be destroyed anyway. Please don't collect plants from the wild, as many plant species have become very rare
due to over-collection from the wild. The wild areas of this Earth are under
enough pressure from human intrusion as it is.
A good way to grow plants from seed is in nursery boxes. These are low
frames placed on the ground, a few feet square, open to the sky but covered with chicken
wire. Henry suggests placing a toad in each to capture slugs that may otherwise want to
devour your struggling young plants (remove the toad in the late summer so it can find a
good place to overwinter!). Cover the box with wood for the winter. When the young plants
have grown enough, transplant them to the main garden.
For trees, it is best to buy small trees. Not only are they cheaper,
but they will grow faster, since they have proportionately more of a root system in
relation to the size of the plant. Larger trees take more time to develop an adequate root
system to support growth.
Henry's pond is about 15 feet long and 4 feet deep, dug entirely by hand. It
is one of Henry's principles to use no motorized machines on his land. It is lined with
heavy plastic to keep the water in. Flattish rocks surround the pond at the top to hold
the plastic in place, as well as to hide it. Other rocks line the sides, with pockets of
soil in between the rocks. All of the rocks came from the property. There is about one
foot of soil at the bottom of the pond, as well as in between the rocks, for plants to
The pond is filled by rain runoff from the metal roof of a nearby shed.
Water comes from the shed roof into a barrel. It overflows from there into a boggy area,
then into the pond.
The boggy area is populated by various wetland plants that like very
wet soil, but not necessarily water, such as marsh marigolds, sedges and cardinal flowers.
Dogwoods overhang the pond edges in a few places along with other shrubs. A few dead logs
litter the pond shores as they would in a natural woods pond.
To get aquatic insects and other life into the pond, scoop small
amounts of water from various ponds and marshes in your local area (no more than a
litre/quart at a time).
Henry advised against putting goldfish into your pond, since they will
eat everything else in the pond, cleaning it out of the natural plant and aquatic life
that you want in it. Besides, goldfish are not native to this area.
One of the main reasons that he built the pond was to invite toads in
during their mating season, to encourage them to breed, and because he likes their
trilling sound. To this end he has been very successful, with sometimes quite a few toads
in the pond at once.
Composting and yard debris:
No bio-material has been removed from the property at all. He has a large
composter in the back of his yard. This is one of the multi-layered types, made out of
wood. He rotates the layers bimonthly.
Branches have been placed in a large brush-pile at the side rear of the
property. This provides good shelter for snakes, small mammals and certain types of birds.
Branches are sometimes burned in small campfires that he has every now and then. Smaller
trimmed branches are placed under the tree or shrub that they were trimmed from.
Henry has imported maple leaves every fall to increase the bio-matter
in the soil. He spreads them by tossing them up in the air over where he wants them, to
emulate them falling naturally. But only as much as might be present in a comparable
An ephemeral spring has arisen at the foot of his property (the property
slopes downhill) since he has naturalized it. This is due to rainwater no longer running
off the grass -- the large variety of plants now allow the rainwater to be absorbed into
the soil, to drain slowly downhill and exit at a natural location at the foot of his
Contrary to common beliefs, the value of Henry's property has actually
risen since he began his project. The house next door recently changed hands, and one of
the main factors influencing the purchasers was the naturalized beauty of Henry's property
Bird life has increased significantly since he started. Over 60 species
- half are migrants only - stay and feed in the yard where no feeding stations are used. A
wide variety of plants helps here. He also leaves the stalks and seeds of plants to
provide feed and nesting material for them. He doesn't "clean up" in the fall,
but leaves the dead plants to decay in their own time as they would naturally.
Henry has created an oasis in the middle of an urban/suburban
landscape. Naturalists and others come from many places to admire the transformation, and
to take inspiration from it. He emphasizes that it's not really that hard to do; anyone
can do it with the will and determination to do it. You don't have to be an expert.
Henry's yard is private property. To see and gain inspiration from a similar
naturalised area you may wish to visit the Gosling
Wildlife Gardens at The Arboretum of the University of Guelph in Ontario (Canada).