About 25 years ago I started making a ‘dry’ garden – one that would never be watered, but would still carry the quality of verdant oasis that I was then addicted to.
Among a whole book of lessons from that experience (and written about in my first book Michael McCoy’s Garden – see details below) was one that started to form back then, and is yet to really clarify for me. What I witnessed was that many drought tolerant plants could absolutely laugh at a hot, dry summer, with no supplementary water, and then tolerate a relatively wet winter, only to turn up their toes and die within three days over a warm, wet spring.
About the same time I was advising on the establishment of a garden in Redesdale, Central Vic, and on the drive home was hit (violently, in my memory) with the truth that the biggest challenge to creating a garden in that setting was not the hot, dry summers – there’s loads of plants that are more than a match for those conditions – but the puggy grey clay in that area that those same drought resistant plants wouldn’t tolerate, particularly when it was wet and warm.
In the intervening years, there’s been nothing but continual confirmation that the vast majority of Mediterranean plants adopted for gardens, and Australian plants that enjoy Mediterranean conditions (of a mild, moist winter and hot, dry summer), come from areas with rocky, gravelly, shaley or sandy soil that, due to its physical characteristics, is both exceptionally well drained and relatively infertile.
Eventually the thought-stream arrived at the curious, somewhat counterintuitive truth that the biggest hurdle to making a dry garden in a climate like that of most of South-east Australia is likely, therefore, not to be the driest time of year (which is ALWAYS how the challenge is presented), but the wettest time of year, and particularly the occasionally wet spring, when plants are growing fast. And that, therefore, the most important modification required to achieve any dry garden dreams is the improvement of drainage, via the addition of coarse sand or other soil-opening particles and/or the installation of surface swales to direct excess water away from the garden, possibly in combination with subsurface drainage such as slotted aggie pipes.
My current garden receives no supplementary watering, and is mostly brutally dry during the mid to late summer, but even then, there are plants such as the exceptional-in-every-way Marlborough daisy (Pachystegia insignia) which will only survive at the top of a west-facing dry-stone wall where it will never have any excess moisture sitting around its roots. It would probably be happier with more moisture than it gets, to be frank, but not if that moisture ever reduced the air around its roots. It may not love being too dry, but it copes with being too dry. It will not cope, at any time, with being too wet. And while Marlborough daisy may be exceptional in its drainage demands, there are very few garden-worthy drought-tolerant plants that will survive spring inundation.
(As something of an aside, the best explanation I can come up with as to why some plants will survive a wet winter only to die rapidly in a wet spring is due to their respiration rate. They’re virtually asleep over winter, and ‘breathing’ slowly, like a hibernating bear. When it warms up, on the other hand, they’re growing like crazy, and ‘breathing’ hard through their roots, so ‘drown’ much more rapidly when oxygen is unavailable due to inundation. Unfortunately I can’t prove the veracity of the theory. I’ve never been able to find anything documented along these lines, so my thoughts are all I can supply)
So, in facing a drier future, and adapting your garden to that new reality, it may well be that the most important thing you need to do is to check, and improve, the drainage.
As for the question of soil fertility, let’s leave that for another post. That’s a whole other ballgame.
Hardcover copies of Michael McCoy’s Garden is still available at $25 + $15 for postage (unfortunately that’s how much it costs, ExpressPost). If you’d like a copy, shoot me an email at [email protected]
New ways of gardening like wicking beds are essential for dry climate growing of edibles. After establishing some wicking beds a few years ago I now ONLY grow green leafy vegetables, rhubarb, herbs like coriander that need lots of moisture, peas, brassicas and fruits like tomato in these beds. In summer we cover them with a 30 % shadecloth too. I’m in Perth and it is very hot and dry!!
Wicking beds are such an interesting case-in-contrary-point. I admit to being philosophically troubled by the idea of deliberately impeding drainage, for any reason, but I can’t argue against the fact that, in the case of wicking beds, it works!
Loved this post and it resonated deeply with the journey we have been on establishing a garden in Brisbane. The challenge to find the right plant choices for both the very wet years and the very dry years is perhaps one of the reasons many gardens here have so little diversity of plant selection. Particularly for the areas like our neighbourhood in heavy clay. A garden that’s resilient to both extremes is indeed the challenge and so very little literature to help.
SO little literature. I’ve always found this to be the case, with any of my burning questions. And you make such a good point – that of the challenge of finding plant choices for both the wet years and the dry years. I doubt that that explains the low diversity of gardens in your area. I’m guessing that that is more to do with a failure of imagination and/or empowering info. Looks like its up to you to lead the way!
YES!! What’s an aspiring gardener to do in Victoria – chances are you’ll land yourself on top of 1cm of topsoil and a slab of clay compressed to the end of the world. At the same time we need to do as little ‘digging’ as possible to preserve what we have, cause as little damage….
yes, what is one to do? Think, dream, experiment, fail. Then keep thinking, keep dreaming, keep experimenting, and perhaps fail a little less often. Repeat for one or two lifetimes. At least
Thank you, Michael, everything you said resonated strongly with me here in North canterbury NZ. The sandy free draining soil I used to lament, and amend, I now see as my best asset. I bless it every day, in our summer dry garden.
I love this so much Jenny. How fabulous to have argued and fought against a blessing. Makes me wonder about how often we do this in other areas of our lives…
Michael, enjoyed reading your latest article and agree with your views re plants breathing UNTIL you mentioned “facing a drier climate”. You lost me there. Weather is weather with cycles within cycles and it has all been seen before over time. The only problem we are facing with our gardens is a lack of stored water with ever increasing population meaning next drought cycle will have devastating consequences for many gardeners (water restrictions). People living in the bush always reliant on weather and own storage generally have plant selection more able to cope but many in cities, towns etc will be in for much disappointment.
Thanks Greg. No matter where you stand on climate change, I think we all stand in a similar place with regard to our obligation to be better stewards of finite resources. So whether the climate is drier, or whether we just need to water less, there’s a growing challenge. Fortunately we’ve creativity to match, that’s really yet to be tapped
Michael, your post relevance is currently on point for many of us right now. Until you asked me which season did I see the greatest loss of plants, I hadn’t given it a great deal of thought. In the 25 year lifetime of our mostly Mediterranean Wimmera garden, 2011 and 2016 were the only times we’d experienced inundation. Since your prompt to ponder last year, the garden has been inundated numerous times and such conditions unquestionably have drowned many plants, bursting with new Spring growth and where drainage is terrible.
Our garden is located along what once would have been a large ancient river; half the garden is on deep sand and the other on shallow mud flats. It’s plantings on the age-old mud flats where we’ve been caught out.
In areas of harsher Summer conditions, we tend to plant for drought hardiness with little consideration for flooding rains. A local native plant genius advises to raise planting beds, but never more than 250 – 300mm or it’s too difficult to retain sufficient moisture to see shrubs through our brutal Summer. 10km away from us where the soil is highly plastic black clay, plants in raised beds hold moisture over Summer and many shrubs continue to thrive when ours have slipped in their Summer torpor. It’s complex!
Thanks Jennni, it was so brilliant to see your garden last week. So inspiring. So many strong lessons there.
Complex? that’s an understatement. I’m overflowing with questions about how to deal with imperfect/suboptimal conditions – how to make small, local modifications (like your local nursery’s suggestion) that might mitigate these moments of occasional stress that can bring a garden down in a matter of days, after a decade or two of happy growth. I so wish there was a greater financial imperative for horticultural research – studies that might show that with soils of a certain measurable drainage quality and/or range of air spaces and/or (add numerous other factors), how much mounding will provide the perfect balance of drainage and access to soil moisture. Or, perhaps, the optimum balance of nutrition vs free drainage of plants growing in pure sand/mineral substrate. SO many questions! But so far I find them more life-giving than frustrating. Thankfully gardening is as nurturing of our curiosity as it is of our plants, hey?
Thanks for this post Michael. Feel lucky to be able to tap into your percolating thoughts and being continually challenged in my garden making. That said, it’s a sobering reminder that this gardening pursuit is not for the faint-hearted. Just sometimes, does anyone else in this little community imagine themselves escaping into the pages of a picture perfect magazine where there is only gardening bliss (and a garden army behind the scenes taking care of drainage, plant selection, erratic weather and its aftermath of heartbreak)?
I’ve spent the afternoon borrowing compost, and trying to deal with questions around how I might have designed the garden better to minimise the time taken for this process, or whether its justifiable at all given everything else I should be doing etc etc etc, all of which add a level of angst to a job that I can’t even pretend I love doing. I frequently end up wondering how it is I’ve been so drawn into this, and whether I could or would love a life in which I could wonder what I should do with the coming weekend… Then at some point in that thought-stream, I am forced to accept, yet again, that I was born for a high-commitment/high-reward life. There’s no point me fighting it. That doesn’t stop me, of course, imagining it otherwise…
Very thought provoking Michael. Last weekend as part of the inaugural and very wonderful Nature Festival here in Adelaide I went along to the Botanic Gardens to hear Tim Sansom speak about gardening in our changing climate. It became abundantly clear early in the talk that it was no longer just a matter of dry garden/hot summers/Mediterranean zone gardening that had to be addressed but how do we cope with wet Winters and Springs as well as scorching summers – as we have her in Adelaide. I pretty well understand and have gardened for the dry summers but am busily building swales to capture and redirect water during excessively wet seasons. Currently my garden has gone gangbusters after 2 weeks of relative sunny conditions here but I did wonder whether I would ever not sink into and slide down our clay paths and slopes after the wettest 5 months in my living memory. I would love to learn more about the balancing act between moisture saturation and baking heat!
Me too! I’m guessing we’ll all be learning this very fast! Roy Diblik – long term grower of prairie plants in North America – said at a recent presentation that climate change will not see us looking for plants for the dry, but for plants more tolerant of variable soil moisture conditions. Hopefully see you in Mount Barker on the 12th November?
We DID meet up at Ukaria on Nov 12, the day of the Great Storm and I even got to speak to you about learning about and understanding that my garden is summer dormant. Have had a great spring/early summer display, cut back most things and now awaiting the second blooming.
Santa delivered your Dream Gardens book of which I rationed the reading. I’m a Primary school teacher and didn’t realise properly that the Principles of Design that I occasionally reference in art lessons are in fact the same principles I was largely unconsciously employing in my garden’s design! Especially unity and balance. I particularly loved the chapter in which you mention that design choices are often enhanced by having less choice. Not at all counter-intuitive for me as I have been saying this to anyone that will listen: until a pool went in to our large backyard taking up an empty flat space, I was unable to start imagining a design. Once in, I had defined spaces with which to tinker and I was away! I really can’t deal with a blank canvas.
Many thanks for everything you do and share in the world of gardening design and plants. I have learnt so very much!