At
the time of writing this there is level 3 water restrictions in place
in my area (Brisbane) which means no hand-held housing whatsoever -
just watering cans. So I got to thinking about garden design and I
looked at a few books and I did a bit of research then I thought: I
have not found the exact type of garden that suits my garden in these
dry times, so I came up with my own, kind of influenced by permaculture
mandala gardens and trench gardens but with the addition of old milk
containers. We'll get to the milk containers in a minute, firstly I'll
describe the scene... Way
out yonder in the back of the backyard, under an old and useless
grapefruit tree that has seen its best day when Mussolini was
a
boy, there is a dryish spot that I'd always thought I should do
something with. I
got to thinking. And I thought and I decided I should dig big round
holes about half a meter deep, about a meter wide and about 50 cms
apart around about the edge of the canopy of the tree (removing any
tree roots I found). Basically when you looked up you could see part
tree leaves and part sky. I then dug a few more holes closer to the
trunk. What
I did with the soil from the holes was simple. I mounded it up around
the outside of the holes so there was a mound stretching the entire
border of the newly dug garden with two entrances at one end so you can
still walk in on flat ground. There was also a fence line border the
back of the garden and some existing plants which helped complete the
border. Basically at the end you could walk around the tree from one
side to the other through a network of paths which 'webbed' out around
the holes. I
then filed the holes with old roughly cut up palm fronds, which
we have in abundance around here, as well as crash clippings,
fresh manure I got from the horse stables near by (which is mixed with
sawdust) as well as cuttings from heaps of other plants like borage,
cardamom leaves, yarrow, comfrey, as well as a little bit of topsoil.
Before I filled it all in I grabbed a few 3 liter plastic milk cartons
I saved and I put a few holes into the bottom and on all four sides
about 5cm from the bottom, and put a bit of yarrow, borage and comfrey
at the bottom. I placed one of these cartons in the middle of
each garden (pouring or right side up) and backfilled with
leaves
and all the above mentioned stuff until the carton's top was just a few
centimeters above ground level. I also placed a few of those red south
American worms which you use for worm farms worms on the top of all the
manure and what have you so they could eat their way around a bit and
help things along. As
for the milk cartons, they mean I can now come along with a
watering-can and fill up each bottle daily and be sure I'm watering
quite deeply. Previously when the ground dried out a bit you'd be lucky
if a watering-can full of water penetrated more than a few centimeters
down, which is not so good for encouraging deep root growth and led to
stress on my pumpkin vines when it came time for them to fruit leading
to loss of all their fruit. It also means a great deal of water is lost
to evaporation before it has any time to sink in.
"You could have just
used mulch", you cry, but mulch often absorbs a lot of the water which
can also lead to waste, you need to get below the mulch, not water it.
Watering mulch does help it to break down, but if you're short of
water, just wait till the rain does that for you. Of course you can
also just water the entire surface area, especially if you have shallow
rooted plants like lettuce growing.
With the milk cartons water either runs down the sides or filters out
of the holes (which also bring some juice of the herbs mentioned which
will help to fertilise in the future - you might also add a bit of worm
castings to this if you like). So really even if you have shallow
rooted plants you could just grown them closer to the center of the
round garden as this will obviously by the moistest bit.
Also the outside mound of soil funnels any excess rainwater into the
outer holes so they benefit from slightly more natural flow-on than
they would otherwise get - from rain and when you water the area
yourself. On the outside of the mound, and on top I've placed
stacks of hardy herbs, flowers and things like cardamom which are
pretty dry tolerant but also look good and are easily propagated. The
idea with these gardens is that due to the very high organic matter
that will breakdown over the next few months and form the 'soil' for
these gardens I will have both adequate drainage for when it pours down
rain in summer plus a good level of water retention all year round. The holes at the bottom
of the cartons are also out of concern for leaving stagnant water for
mossies to breed in. If water is staying at the bottom for too long you
might want to consider more holes or replacing your milk
cartons
as the holes have probably blocked up. The
icing on the cake will of course be more mulch (about 15 cm) of lucerne
hay and sugar cane mulch (and perhaps a little chook manure and
dolomite) . Come
back later when the plants have grown so you can see a few photos. I'll
add them as I get them. In hot summers with little rain, or for those
plants with high water requirements, you might want to fill up the
containers twice a day. Good
luck in the garden and don't worry about your hose, with this method
you won't need it.
POSTSCRIPT: After
experimenting with this method for some months I have found it indeed
allows moisture to be maintained in the soil even in very dry spots. I
did get huge pumpkin vines growing but they did not set fruit - though
I have had problems in this (geographical)area with pumpkins not
setting fruit and no method I have employed has been able to counter
this. I have had a very successful plantings of basil, capsicum, lemon
grass, lettuce, sweet potato,potatoes, bush beans and rocket using this
method, even though we have now entered level four water restrictions
and I have virtually left some of the areas without any water at all (I
did water to establish and we have had a little bit of decent rain). I
have also found along the way that this is a good method for
establishing larger trees and plants and I have a little paw-paw
(papaya tree) emerging where I once had the pumpkin vines. I have also
found that it is better to have one larger milk carton in the very
middle of the little gardens rather than having several smaller ones.
Hope this method works for you - one adaption you might like to make if
you are in a colder climate is to add a layer of very fresh manure at
the bottom. Someone I knew at university tried this out in Sweden and
he says that it warmed up the patch so plants like tomatoes could be
transplanted out a little earlier than would otherwise be possible. He
also recommends putting coffee grounds around seedlings susceptible to
deers as the deers associate the smell with hunters and avoid your
garden.
