With an El Niño looming large this summer, sustaining garden production between now and next May is sure to be a challenge.
We all know about mulch -- but where do we get it?
A water tank only goes as far as it is deep.
If drought hits big time we may return to water rationing. It is well worth remembering the past:
From 2001 until 2010, Brisbane and surrounding temperate areas had been experiencing the most severe drought in over a century, with dam levels dropping to 16.9% of their capacity on 10 August 2007. Residents were mandated by local laws to observe level 6 water restrictions on gardening and other outdoor water usage. Per capita water usage is below 140 litres per day, giving Brisbane one of the lowest per capita usages of water of any developed city in the world. On 9 January 2011, an upper low crossed north of Brisbane and dropped rainfall on an already saturated southeast coast of Queensland, resulting in severe flooding and damage in Brisbane and the surrounding area; the same storm season also caused the water storage to climb to over 98% of maximum capacity and broke the drought. Water restrictions have been replaced with water conservation measures that aim at a target of 200 litres per day/per person, but consumption is rarely over 160 litres. In November 2011, Brisbane saw 22 days with no recorded rainfall, which was the driest start to a November since 1919..[REF]
So I'm wondering how folks are preparing for the likely dry to come? Am I missing anything, I'm wondering.
My reading of the garden experience this year is that while it has been hotter than last year over Winter, there has been more precipitation and generally less drying wind...so outback is in better nick that this time last year. I recall an October scorched earth event --12 months back -- that devastated my vulnerables.
So now I get anxious.
It seems to me that over the Summer heat -- and any likely dry -- the priority response -- the first aid -- is a ruling hierarchy:
WATER:I have a 3,000 litre tank. I've learnt that if you don't use it you loose it. So I make sure I rely on tank water whenever it's in the can. It's an improvisational approach with one eye on the weather and one finger in the soil. My terracotta pots take 2.5 litres each and anything else is splash around hosing. But I need the hand watering to maintain the system. Nonetheless, with tank water, hand watering, etc , despite the huge veg garden, our domestic/town water consumption is way below average: always under 200 litres/day overall. I recycle water from the kitchen and toilet flushing is minimal.
MULCH: despite the weather, over Summer the grass grows and grows. So I get plenty of lawn clippings which I use sparingly.Depth matters in the heat. Knowing where to spread the latest drop off from mower folk is an art. But I think carpet mulching is over rated as a measure against evaporation.Essential -- especially for seedlings and adding fibre to the soil as well as for weed suppression -- but only one aspect of a broader water budget strategy. However, i keenly mulch my 'valleys' with paper and other detritus in order to convert them into bogs retaining water.
SHADE: While a relative thing -- and various over any one day -- I'm respecting shade more and more. I've given up on shade structures (which suffer so much during the storm season)and look to target plantings to engineer the tone down. I planted frangipanis* with shading in mind but they aren't fast (enough) growers.So this Summer, I've turned to placement plantings of Pigeon Pears and aerial fly-overs of climbing plants as my key umbrella tools. I'm also more conscious of integrating shade with my watering habits by hosing shaded earth rather than scorched earth.
SELECTIVE PLANTINGS: The big irony is the more the merrier.With all my up and down contours, I've discovered that dense plantings act as a powerful coolant and moisture retainer.A 'rainforest' doesn't have to be tens of metres high. it can be a mixed bunch of annuals, even short ones, growing in the one densely planted space. As well as planting out edibles I'm using a mix of other plants to fill the spaces. This 'jungling up' effect makes the plants symbiotic as ambience is orchestra driven. In the gaps I'm relying on pigface a lot which I also harvest and chop up as a buried mulch to improve the sandy soil's water retention capacity. I suspect -- if this does indeed work -- that many other succulents, like aloe vera, would work the same way.
GARDEN CONTOUR: Ah the big adventure -- the mounds. Aside from the Summer Solstice, any one of my mounds is going to have a shaded side for part of the day. So many of the plants growing there have the chance of some relief from the un-relenting sunshine at least for part of the day. Research on traditional mound gardening confirms the temperature variation on the north/south axis. Contours also act as swales -- directing water underground and preventing run off. However, my experience also suggests that up and down contours also trap dew fall and hold onto night time cool longer into the morning because they sponsor a valley effect. With cool valleys and warmer hills you get a keen microclimate going. I don't understand this up and down effect but I'm impressed with its qualitative impact on the plant orchestra.
As the Summer descends I'm relying on a few markers to tell me how I'm combating the heat and the dry.
* frangipanis: While they are not fast growing they are deciduous and thus far, I have had no problem with their root systems. Easily grown from cuttings and wondrous when in flower they are also easily managed: you can trim them with your bare hands.
I'm glad I'm not the only person who remembers that mini-drought last spring. My garden was decimated by the lack of rainfall and sudden heat. This year has been very mild in comparison, despite the El Nino factor. Of course, November hasn't even arrived yet and it's still possible we won't get a drop of rain until Christmas.
I'm going to be getting a water tank connected to downpipes in the next week or so. I'm in a rental, but I got the tank from a neighbour who didn't want it any more and couldn't be bothered selling it and the gutters on the house need replacing, so the landlords are going to get the tank connected at the same time for (hopefully) relatively low cost.
I'm coming around to the importance of shade as well. The pigeon peas I have planted in the middle of the lawn are surrounded by high, lush grass which is in stark contrast to the lower, browner grass everywhere else. I have used New Guinea bean as a shade plant before, growing on my possum netting, but I haven't figured out how to make it work for my new netting-free garden.
And given the crazy nature of probabilistic prediction, the rain outlook is only ever expressed in term of an x% chance of above average rainfall. That means that even in the worst El Nino there is still a small possibility of getting plenty of rain, just due to the stochastic (probability-dependent) nature of weather.
I've been here 7 years I think -- gardening the same patch for 7 years under the same sun, year in year out, all seasons.So you begin to comprehend the habits of the atmosphere and the way the elements address your patch.
I've got to appreciate the tree lines over the fence, the fences themselves and my own huge Silky Oak. Since shade moves its reach diurnally and annually it is a relentless variable.
I'm not really a follower of the standard categories -- shade, part shade, full sun -- because shade is so relative. I think 'morning sun' and 'afternoon sun' are more useful markers. Even in Summer there are workarounds.
This Winter passed was really Spring with cool nights.
Nonetheless, the 'mini-drought last spring' was a shock. It required first aid I was not able to give.I was interstate for part of it and on my return after a week away the death and destruction was appalling.
So I'm getting in with the protocols early: preparing for the worst or the sudden shift to brutal.
The school garden we work at, which has no shade at all, is already frying under the unrelenting warmth. The salad greens there are rushing to seed. Plants are wilting. Exposed cucumbers are singing.
The problem with growing your shade requirements is that you have to have imagination and project growth and growth rate onto a landscape on which the sun rays are constantly moving. I reckon Pigeon Peas offer the option of not only being quick growing with mottled shade effectiveness, but they can easily be cut back because there are plenty more to be had.
The also work off one deep tap root so they won't take over the bed.
Ditto for many climbing annuals.
I had grown pawpaws in the garden with a mind to shade and they were a disaster. I thought, as short lived perennials, they were a handy option. But their roots stretched all about like tentacles. Being an up and down plant, I was not getting much shade out of them either.
Not that I've got any standard beds anymore, but when I did, I built railings -- 'hand' railings at waist height -- along their length. These have been very useful for anchoring climbers before I run them skywards on twine. But I guess they also offer me the option of draping shade cloth over them, tent fashion, if things get really hot and the PPs aren't fulfilling their promise.
I go for dense planting to shade plant roots.When I see a sparsely planted garden I just want to get in there and remedy that situation with more plants.
I have some netting that I can throw over frames on the raised beds for shade, if needed. I prefer to choose plants to suit a situation. Shade loving under/behind something bigger and hardier for instance.
My 5000lt rainwater tank supplies nearly all my garden water needs and the plants seem to prefer natural (as opposed to town) water. I like to hand water - its one of life's simple pleasures which also allows me to check out exactly what is going on in my garden world.
I gotta get myself some netting...sure to be much more useful for draping than shade cloths which can be cumbersome/hard to manage.
VegeNet is I think a brand name but vegenet is a generic term for woven/knitted(?) white poly-something fabric to throw over plants. It's about 18% shade and with plenty of small holes is reputed to give good ventilation. All I could find is cut lengths. Seems you'd have to buy many kilometers to get it in a roll. Eventually I bought mine from WA, and got as much as they could cram into a 3kg postbag. The prices vary a lot with Green Harvest probably the dearest. I've not used it so far but from what I read, veges/fruits do very well under it with the shading and keeping in of moisture plus keeping out the bugs.