From the age of three, I was digging nasturtium and tomato seedlings out of Dad’s compost bin and planting them in the garden. That interest never waned and so as I was growing up, one of the very special treats I got to enjoy on certain school holidays was a trip to Gardenworld in Braeside.

Gardenworld is a sprawling horticultural complex established by the Jackson family and consisting of seven independently-owned businesses that each specialise in different products or greenlife. For a small child fascinated by plants, it was like a theme park full of places to explore and all sorts of peculiar plant species.

By far the most iconic part of Gardenworld was the enormous cactus that stood at the main entrance to the complex, near the Gardenworld Café. It was absolutely enormous, and I assume it must have been quite old because it was propped-up with an elaborate assortment of steel poles, stakes and ropes.

What used to fascinate me as a child in the early 1990′s, sitting in the café with my meat pie and iced coffee, was the string of Japanese tourists who would come via bus and have their photos taken beside that cactus. For whilst Gardenworld was certainly well-known to keen Melburnian gardeners, it seemed odd in a pre-internet age that foreign tourists would even know of the existence of Gardenworld, let alone make a visit in a bus.

I shot the above photo of the front of Gardenworld in 1999. I think it might have been my last visit to Gardenworld because I’d started university that year and also acquired a job in a retail nursery far closer to home.

Just recently, Gardenworld re-entered my conscience and so last week I decided to make a long-overdue trip back to a place that had meant so much to me as a child. I didn’t really know what to expect, but thought it might be fun to take another photograph from the same angle that I’d take the ‘cactus’ photo in 1999:

As you can see, the large cactus has gone and the rolling lawn has given way to a maze of raised beds containing a selection of succulents. I am guessing that the lawn disappeared during the crippling drought.

My first stop at Gardenworld was Collectors Corner, a large business that sells a range of orchids, cacti, succulents and bonsai. Apparently Collectors Corner started at Gardenworld in 1984 and was rebuilt and expanded in 1987. Collectors Corner is almost as big as the Gardenworld Nursery itself and was always a source of fascination to me as a child.

When one enters Collectors Corner, they are greeted by a range of beautiful orchids, bromeliads  and other tropical species which look so spectacular. I was pleased to see that the place hadn’t changed too much from how I remembered it.

It’s pleasant to walk the aisles, looking at the beautiful orchid species including Cymbidium, Dendrobium and Phaelenopsis. Collectors Corner is a serious business and so they have some serious facilities such as this beautiful but very humid orchid room:

The stock must be very valuable because signs warn of security cameras everywhere in that space. In fact, there is even a caged section where the rarest of rare species are offered for sale behind lock and key!

As one leaves the orchids, they progress to the cactus department. As a child, I always had a special fascination with cacti so this was a particular highlight. The cactus sales space was exactly as I’d remembered it, with row-upon-row of tiny pots for sale with every imaginable species of cactus on offer.

Like I did when I was a child, I walked every aisle, looking at all the various cacti.

One feature that has changed since I visited in 1999 was the cactus display garden.

One of the loveliest features at Collectors Corner are the display beds where one can see many of the species growing in a landscaped environment. I believe this also serves to house the proprietor’s personal collections.

When I used to visit in the 1990′s, there was a large hot shed with a clear roof that contained a large collection of cacti. One could walk along the paths around a small circuit and examine some massive prickly specimens. I recall being particularly careful to ensure that I didn’t trip over and fall because I could imagine myself tripping face-first into a barrel cactus!

The shed used to have a lovely trompe-l’œil on the wall which added to the impression that one was walking through an American desert. The shed has now been demolished and a new shed built in a slightly different location. Whilst being a larger space with a bigger collection of plants, it lacked the trompe-l’œil that gave the old space so much character.

From the cacti, one proceeds to the tropical species which includes Tillandsia, bromeliads and carnivorous plants.

One of the nicest spaces in this section of Collectors Corner is the small walkway through a mini ‘rainforest’ that is filled with many fascinating species. The walk even crosses a bridge over a ‘waterfall’ and ‘creek’ to a pond filled with fish. Unfortunately the waterfall wasn’t switched on when I visited, but I was really pleased to see the rest of this feature had been retained just as I could recall from my youth.

The combined and distinctive smell of humidity and moist potting mix is as evident here as in any glasshouse one is likely to enter. For me, it simply adds to the atmosphere.

The next section of Collectors Corner that one encounters is their significant collection of bonsai.

I was always impressed with their bonsai collection and even as a child, I understood that they must have been worth a considerable sum of money. The entire collection is housed in a yard that is bounded by a high fence topped with barbed-wire.

Some of the bonsais are literally chained to the pot and the bench that the pot is housed on, such as this amazing Monterey pine (Pinus radiata) that was sown from a seed in 1948.

The area consists of some very old bonsais, as well as smaller and newer plants for sale. I simply don’t know of another nursery in Victoria that has such an extensive range of bonsais of varying ages and species. It’s a real pleasure to wander the aisles and look at each individual work of botanical art.

Compared to my last visit in 1999, this area has changed somewhat. Having looked at the site via Nearmap, it seems that the space has been reduced in size and a new fence erected to accommodate works behind the nursery. There was still some building work occurring at the back of this space when I visited.

Of course, after so much horticultural exploration it’s time to proceed to the Gardenworld Café for something to eat.

When I used to visit as a child, my morning tea choice was always an iced coffee and a meat pie with sauce. Sitting there this time with a latte and slice, I was reminded of how things had changed.

Where once a few tables were arranged on a small area of brick paving under a giant Canary Island Date Palm, itself under-planted with Impatiens now sits an expansive decking area complete with café umbrellas. When I was a child I could see tractors ploughing fields on the other side of Springvale Road, but not any more. There are houses there now. The interior of the café used to have beautiful large pots of nodding violet (Streptocarpus caulescens) and these have gone too but otherwise it’s not too different, save for some minor redecorating internally.

From the café, it’s time to walk past Collectors Corner to the other parts of the Gardenworld complex. There used to be a soil supply business called “Soil’n'Spade” whose driveway we had to cross, but this seems to have disappeared. In its place is an expanded yard for Lotus Watergardens who specialise in aquatic plants, ponds, water features and the like.

I recall when I used to visit in the 1990′s that Japanese “deer scarers” (shishi odoshi or 鹿威し) were all the rage, but I could only see one on this visit and that specimen had somewhat rotted and was not operational. I do chuckle because for all the selling they did in those days, I have never actually seen one in anyone’s garden!

Next to Lotus is a hydroponics shop called Autopot Hydroponics. I am not sure if Autopot Hydroponics is the same business as the one that used to operate there. I do recall that aside from hydroponics, they also sold glasshouse systems and I recall as a child that I used to desperately dream of having my own glasshouse one day. For some reason Santa never did give me a glasshouse!

From Autopot, once proceeds to the actual Gardenworld Nursery. Even within the nursery, there are several businesses including One Stop Sprinkers and Semken Landscaping (a landscape architecture firm). But for me, it was the plants that were of primary interest.

Perhaps of the entire complex, the biggest changes were within the Gardenworld Nursery, especially the shop.

The large part of the floorspace within the shop that was once dedicated to plant stands, propagation equipment and sprinkler bits has been replaced with garden furniture and ornaments. This is not a phenomenon unique to Gardenworld by any means. I used to work at another retail nursery and witnessed the same trend during the time that drought-induced water restrictions were imposed and sales began to fall. Such a move became a commercial necessity. Other minor alterations had been made  to the shop layout and to some of the entrances and exits.

As for the nursery, nothing much had changed with the exception of a decade’s worth of new cultivar releases. The nursery was still laid out as I recalled and the quality and diversity of stock was still very impressive.

Back in the 1990′s, Gardenworld Nursery used to sell lovely enclosed wooden gazebos that could almost serve as a small building. They used to have one of these as a central ‘help desk’ within the nursery, but I noticed that it had been removed for a more modest desk that was unattended when I visited.

When I was a child, I used to especially like looking at the flowering seedlings. They were always available in such nice colours and new cultivars were being released all the time. I used to use some of my pocket money to buy a few punnets of seedlings (as well as other potted plants) to grow in my garden at home. Even as an adult, I still enjoy potted colour!

In the past 20 years, the Victorian nursery industry has changed a lot.

Where once the sector was dominated my small family-owned business that made Gardenworld a lonely giant, there has been a lot of consolidation with the entry of Bunning’s into the market. A combination of increased competition and drought meant that a lot of the smaller non-specialist nurseries disappeared. As was alluded-to before, many nurseries have had to diversify in order to stay in business.

It is therefore satisfying to see that this great horticultural enterprise has retained the charm and diversity that made it special, especially to a young boy fascinated by plants. I am not just happy for nostalgia’s sake, but I genuinely believe that Gardenworld is one of Melbourne’s ‘hidden’ gems. It has something for everyone.

If you enjoy gardening at all, I highly recommend a visit to Gardenworld. If you do make the journey, make sure you take your children too!

Gardenworld is located at 810 Springvale Road in Braeside and is available on Twitter via @Gardenworld.

Bedding plants aren’t popular like they used to be. I believe the 13-year drought had a lot to do with this, which is a pity because regardless of their water consumption, bedding annuals put a smile on everybody‘s face, guaranteed.

Winter may seem a dull season, but it needn’t be if the correct plants are selected.

To colour my balcony (and impress my neighbours), I selected cinerarias (Pericallis ×hybrida cvs.), primulas (Primula malacoides) and pansies (Viola ×wittrockiana cvs.) which I believed would provide good colour throughout the winter months. All were planted in March and are now a spectacular blaze of colour.

My balcony has an easterly aspect, and so receives direct sun for about 50% of the day. All of my plants were grown in planter boxes containing fresh Debco Premium potting mix. One shouldn’t recycle old potting mix (there’s a risk of pathogen spread) and buying cheaper products that don’t meet the Australian Standard will lead to disappointment.

The first of my three seedling species to flower were the pansies. I bought an extremely cheap punnet of mixed colours from Bunning’s Warehouse but as it happened, the buds only emerged with either pale blue or white. Whilst it looks lovely, it wasn’t what I had in mind!

Pansies grow to about 20 centimetres in height and width. The key to keeping them looking good (and producing more blooms) is to remove any spent flowers as soon as they’re spotted. That way, the plant will be encouraged to produce more blooms and there won’t be a visual blemish from withered flowers.

The most spectacular of my blooms are the cinerarias, although these were the last to emerge. Unlike pansies which constantly produce new flowers, cinerarias develop one large inflorescence of blooms which are available in white through to pinks, purples and blues. Just as I did for the pansies, I bought a cheap punnet of mixed seedlings and got blues and pinks.

My cinerarias stand about 30 centimetres high and look stunning. Unfortunately they proved to be extremely popular with a range of caterpillar species and whilst I chose to physically remove the caterpillars (with a limited degree of success), the best remedy for them is actually an application of Dipel®. This is an organic product  containing the bacterium Bacillus thuringiensis which is poisonous only to caterpillars, so it provides an excellent natural remedy that doesn’t rely on chemicals or harm anything else.

Fortunately the caterpillars have left the flowers well alone. The blooms are now so large that the leaves are difficult to see anyway. That said, I can see a lot of caterpillar poo on the pavement below, so there must be more of them in there somewhere!

Perhaps the most delicate but plentiful blooms I have enjoyed are those of the primulas. Primulas are normally available in pinks and white, but I chose a selection of all-white seedlings which I felt would compliment the bright colours of the pansies and cinerarias.

Primula malacoides produces upright inflorescences containing whorls of small blooms in horizontal arrays. Each plant has foliage to about 15cm in height and flowers to 30cm with each plant producing multiple inflorescences. Planted in a cluster, they look amazing with a gentle breeze blowing through them!

In addition to my bedding annuals, I also have some dwarf cyclamen growing. I especially like this fiery red one:

Along with my green rose (now in a semi-dormant state), azaleas, cycad and various species of Thomasia, my balcony is quite a sight to see. Whilst it is very tempting to put up a photo of the whole display, I shall refrain for privacy reasons but I can say that I have seen numerous people stop and admire the plants, which is immensely satisfying.

Satisfying too is being able to sit at my table and look across at the colourful display with a latte in one hand and book in the other. But only if the winter weather is warm enough!

When these plants have finished in September, it will be time to plant my summer annuals. I am unsure what I will choose for this year but I have plenty of time to think about that.

The historic boulevard, which commemorates the town’s war dead, was planted in 1918 and consists of 312 trees and 3.3 kilometres of road. Between 10 and 12 trees will be removed under the proposal.

The trees are Dutch elms (Ulmus ×hollandica), grafted onto either U. procera or U. glabra. Not all of those 312 trees commemorate war dead, but there is a dedicated section which consists of the 1918 plantings. There are some older trees at the town end from a series of plantings in 1880, and a younger section of trees planted in the 1960′s for a road realignment.

The Bacchus Marsh ‘Avenue of Honour’ is one of the oldest and most magnificent in Australia, being the catalyst for similar avenues that emerged in many towns and cities after World War 1.

What’s proposed?

The State Government of Victoria, through VicRoads, has been granted stimulus funding from the Commonwealth Government to re-align the Western Highway around Arthur’s Cutting, which is a particularly steep and dangerous section of road.

According to The Age, the works will also include extending Woolpack Road north to the Western Highway, which will enable motorists to bypass half of the Avenue of Honour from the eastern (or Melbourne) end. The works will include the creation of a four-lane road, and a round-a-bout in the middle of the Avenue, which will see the removal of at least 12 trees and the addition of lighting. The round-a-bout will be of sufficient size to enable B-Double trucks to enter.

The National Trust is particularly concerned about the plans, as is the Shire council. The Trust says that the Avenue is of national significance because of its over-arching canopy, intactness, the curvature in the road and the historical and cultural significance of the plantings. Owing to Dutch Elm Disease, which has decimated European elm plantings, Australia remains as a disease-free refuge, and therefore hosts some of the finest remaining plantings in the world. (You can read the Trust’s full statement here).

The Victorian Heritage Council does not list the Avenue of Honour on the Victorian Heritage Register, but it is listed by the National Trust and the Shire of Moorabool is keen to have it listed on the Register of the National Estate. In 2004, the Shire of Moorabool drafted an extensive Strategic Management Plan for the Avenue, which provides a wealth of information. The full report can be downloaded here.

Unfortunately, there seems to have been considerable secrecy surrounding this project, perhaps because the State Government is aware of the outcry that could materialise? The Avenue of Honour is much-cherished by the people of Bacchus Marsh, and Victoria. The National Trust have complained that neither themselves nor the Returned and Services League (RSL) were consulted about the proposal until November 2009, whereby it was presented as a fait accomplis.

Work is to commence this month, but still there are no maps and illustrations available on the project website. (As an aside, it seems ironic that there are no plans available for this project as part of the Victorian Transport Plan. Is secrecy part of the plan, too?)

The Minister for Planning has the power to ‘call in’ the project, but instead Mr. Madden has exempted it from various planning and environmental checks (source). Part of his justification for exemption is that the project is urgent, and acknowledges that “third parties will not have formal submissions to the planning authority”.

Saving the Avenue of Honour

The experience of driving the length of the Avenue of Honour is unparalleled. On both sides of the road are market gardens and orchards, which can be seen between the tree trunks. Above, the sky is concealed by a deep canopy of leaves. In Autumn, the Avenue is especially magic as the golden colour of the leaves develops. I have taken several international visitors to the Avenue of Honour, and all have been impressed.

In my view, the desecration of a war memorial is a disgrace. But worse still, the prevention of public participation in the planning process is outrageous in a democracy.

I believe that the Western Highway realignment should progress. That section of highway is dangerous and difficult to navigate. However, the widening and extension of Woolpack Road should be put on hold immediatelty until such time as an opportunity for full public consultation is provided, a heritage assessment performed, and an alternative road plan generated.

It has taken 92 years for the Avenue of Honour to become what it is. I certainly hope this plan is abandoned, because any damage that’s done now will take another 92 years to repair. And if that’s the case, most of us won’t be here to appreciate it.

So I can only conclude that the people of Mount Gambier in South Australia have an easy-going nature and a great sense of humour, because it was there that I recently visited the most peculiar garden I have ever seen in my life: The Umpherston Sinkhole.

Yes, even its name is odd.

But the name is very fitting for a garden that made me laugh at its sheer absurdity and fall in love with its beauty and novelty.

What is the Umpherston Sinkhole?

The Umpherston Sinkhole is named after James Umpherston, who established the garden in 1884. Umpherston purchased a farm property in Mount Gambier in 1864 which contained a large sinkhole (or cave remnant).

Thousands of years ago, the sinkhole had been a cave that had formed because parts of the Mount Gambier limestone had been dissolved. When the top of the cave chamber eventually collapsed, a large open pit (called a sinkhole) was formed. The Mount Gambier district has hundreds of such caves and sinkholes; there are even some in the city centre!

Umpherston used the sinkhole on his property as the basis for his garden, which he named “The Caves”.

Being retired, Umpherson wanted to create for the people of Mount Gambier “a pleasant resort in the heat of summer”. So he set to work clearing the existing vegetation off his property and from within the sinkhole. He carved a path in the side of the rock and erected a set of wooden steps so people could comfortably enter his sunken garden, which he planted with all sorts of ferns, shrubs and flowers.

The garden was an immediate success and became quite famous. People from Mount Gambier and surrounding districts would frequently come and visit. The sinkhole originally had a lake within, and Umpherston even organised boat rides for interested people.

James Umpherston died in 1900, and his garden fell into disrepair in the following years. In 1949, the South Australian Woods and Forests Department purchased the property and established sawmills nearby. As the water table dropped as a result of agricultural activity, the lake disappeared.

By 1976, the garden was nothing more than a ruin and a rubbish dump. It was at this time that staff from the Woods and Forests Department decided to restore Umpherston’s legacy.  Slowly, they removed the rubbish and cleared the weeds. Umpherston’s terraces were still there, and so the staff restored them and planted hydrangeas and other species along each row.

Once again, the garden was a hit with the people of Mount Gambier. In 1994, the South Australian Forestry Corporation (as the Woods and Forests Department had become known) handed the garden over to the City of Mount Gambier, and in 1995, the garden was added to the South Australian Heritage Register.

Visiting the Sinkhole

Visiting the sinkhole is a unique experience. A long ramp provides the initial entry point, which is followed by a set of enclosed steps. It is from here that the first real view of the Umpherston Sinkhole can be seen – and what a view! Being barely a third the way into the sinkhole, it provides a great overview of the entire garden, which beckons below. The sinkhole is round, and from here one can see the various terraces in the garden.

One then descends to the sinkhole floor, where hydrangeas and tree-ferns greet the visitor. The sinkhole ‘walls’ are garnished with a ‘wallpaper’ of hanging ivy, which partially conceals the jagged rocks that surround the garden. Whilst there’s no longer a lake, there is a fountain that operates periodically.

Wandering the terraces offered many different vantage points to appreciate the garden. Children also seemed to enjoy running across the terraces, and it made an excellent location for them to enjoy a game of ‘hide-and-seek’.

After Sunset

As dusk approached, I noticed more and more locals arriving with bags of bread or fruit, and torches as the garden became illuminated. Initially curious, I soon realised what it was all for. Each night, several dozen possums emerge from the shrubs and rock crevices and each night, the locals take food for the possums in the garden.

Everyone seemed to be having a great time hunting for possums with torches, and watching them eat the food provided. Of course, having been so well fed, the possums had become quite particular about what they would and wouldn’t eat!

Umpherston’s Legacy

One one level, this really is the most ridiculous garden I have ever seen. Viewing it with 21st-century eyes, one can only be surprised at this horticultural folly and quite reasonably ask ‘How could anyone ‘destroy’ such a natural wonder, and turn it into this garish pleasure garden?”.

But this isn’t a 21st-century garden. It’s a 19th-century garden, created in a period before conservation laws existed. And perhaps we should be grateful that such laws didn’t exist, or we’d have been deprived of such a wonderful public space.

As a person with horticultural qualifications, I readily acknowledge that this garden lacks botanical interest. There’s nothing particularly special or eye-catching about the common mop-top hydrangeas (Hydrangea macrophylla cv.), tree ferns (Dicksonia antarctica) and ivy (Hedera helix) that dominate the plantings in this garden. But seeing them used in such a creative manner and in such a unique context makes this a most desirable garden to visit.

So what does this garden say about Mount Gambier? This garden showed, above all else, that it is cherished by the people of South Australia’s second-largest city.

Watching parents take their small children along (as their parents had done for them) was a delight, especially given how much the children enjoyed the garden. Teenagers were appreciating the garden too, as were some elderly residents that came out just to see the possums. Tourists from Asia and Europe were astounded at the novelty of the garden and were taking plenty of digital photos to show their relatives back home.

There are few places that will bring all of the diverse sections of a community together, but the Umpherston Sinkhole does just that.

Surely, as James Umpherston looks down from above, he’d be delighted to see that his garden is still enthralling the people of Mount Gambier, 120 years after its creation. As he’s hoped, it is a most special place indeed.

Getting there: The Umpherston Sinkhole is located on the Jubilee Highway East in Mount Gambier, South Australia. Entry is free, and the garden is open from 6am to 1am daily.

The photograph was of a topiarised specimen of Chamaecyparis lawsoniana, which I Christened the “Happy Conifer“.

The shrub grew in the the front garden of a house in Vermont South. Seeing it again, a smile immediately came to my face, not just because of its appearance, but because of the story that lay behind the Happy Conifer’s creation.

^{The Happy Conifer in Danielle Court, Vermont South. Photographed by the author in 1999.}

As you can see from the photograph, the conifer had been clipped into a lovely big face, complete with bristling big eyebrows. Standing on the corner of two streets, it almost appeared to have a personality of its own.

Despite its jovial appearance, it is the story behind this topiary’s creation that I find most interesting. For the Happy Conifer was in fact a happy accident of sorts.

The owner of this property (whom I don’t know personally) appeared to be very keen on growing conifers. In fact, his entire garden consisted of hundreds of different species, all beautifully trimmed into neat shapes. Sometimes I would see the owner trimming his plants, standing atop a trestle that he’d especially erected for the purpose.

Clearly, I was not the only person who’d noticed his dedication to horticultural art, because someone with a more devious motive made a decision to do some topiary of their own.

The Happy Conifer is Born.

One Sunday morning when I was passing by, I noticed there’d been a sudden change in the landscape.

Maybe it was drunken Saturday-night prank? Maybe it was just a dare or an act of coniferous jealousy? Whatever it was, I quickly noticed that someone had passed-by under the cover of darkness and hacked a giant face into the conifer. Appreciating the effort that went into this garden, I felt somewhat sorry for that poor man who spent all the time clipping his plants. Yet at the same time, I have to admit to being somewhat amused because it really did look funny.

I was expecting that the gardener would probably let the face ‘grow out’ and write it off as a nasty act of vandalism. But instead, it seems he may have been amused too because rather than disappearing, the face underwent some ‘plastic surgery’ over the next few years. Slowly it was transformed from a few crude shapes into a piece of sculpture!

Obviously, I was not the only resident curious to watch the transformation. Another local resident went to the trouble of submitting a photo to the Burke’s Backyard magazine in 1998. Norma Shaw’s image, reproduced below, clearly shows the Happy Conifer during its transitive years.

^{A photograph of the Happy Conifer by Norma Shaw,which appeared in Burke’s Backyard magazine in 1998.}

After many many years of amusing Vermont South residents, the Happy Conifer met its demise not too long ago, in a storm. It has since been removed. Having myself moved away from the area, I have no idea whether the same people still live in that house in Danielle Court,  Vermont South.

Nevertheless, having brought a smile to my face, I thought it only reasonable to spread the joy to others; the sort of joy that only a shrub with a face can provide.

In celebration of this event and as part of the Melbourne Design Festival (who sponsored the Melbourne Open House), the Melbourne Central Shopping Centre have commissioned famous French artist/botanist Patrick Blanc to create a Mur Végétale or “wall of plants” in Melbourne.

Patrick Blanc’s “Le Mur Végétale” at Melbourne Central.

Measuring a massive 40 square metres, this amazing vertical garden features a range of ferns and tropical species including African Violets (Saintpaulia) and bromeliads. The garden is mounted on the wall beside the historic Coop’s Shot Tower building under the huge glass dome at Melbourne Central.

Whilst Le Mur Végétale would be able to utilise some of the natural light in the shopping centre for photosynthesis, supplementary lighting has been provided to permit better plant growth and to highlight the artwork.

Living plants clean the air at Melbourne Central.

I really enjoy art like this. It’s detailed, its unique, it’s attractive and it’s eye-catching.

As I walked past the work today, I noticed many shoppers were stopping to admire Blanc’s living artpiece, which surely must have taken months of planning and execution.

Shoppers enjoying “Le Mur Végétale” at Melbourne Central.

Blanc has become famous the world over for his elaborate vertical gardens. The botanist cum vertical landscape designer is probably best recognised for his living wall on the Musée du Quai Branly in Paris, but has completed dozens of other projects internationally.

Le Mur Végétale is a three-part system consisting of a PVC layer, felt, and metal frame, providing a soil-free self-supporting system light enough to be hung on the wall and weighing less than 30 kilograms per square metre. Cuttings, seedlings and mature plants are then added to create the living vertical garden.

In a recent lecture given at the Federation Square and reported on the MIDF blog, Blanc explained that he’s first and foremost a botanist who approaches his work from a scientific perspective rather than an aesthetic one. The positioning of plants is as much about allowing each to receive an ideal amont of light with consideration given to the requirements of each species used, before any aesthetic considerations come into play.

Looking past “Le Mur Végétale” to the historic Coop’s Shot Tower (left)
and a young woman enjoys a rest beside the vertical garden.

Whilst these gardens technically have the capacity to continue growing in perpetuum, it is unclear whether the Melbourne Central installation will be a permanent fixture or not. The MIDF blog claims that the fixture will be permanent and I do hope they’re correct.

If true, there would certainly be a lot of ongoing work required to maintain this garden over an extended period, ensuring the survival and/or replacement of all the specimen plants periodically, and ensuring that the plants are fertilised sufficiently.

That said, Blanc’s artwork brings considerable environmental benefits. Aside from carbon assimilation, all of the water used in Le Mur Végétale is routinely recycled, having been sourced from the centre’s airconditioning units.

“Le Mur Végétale” is located adjacent to the historic Coop’s Shot Tower.

Regardless of the longevity of this particular work, it’s been great to see one of Blanc’s amazing vertical gardens here in Melbourne. It’s certainly added a unique talking point to the Melbourne Central Shopping Centre.

Acacia glandulicarpa.

This year I’ve been surprised to discover most species of Acacia blooming in mid-July. In fact, I even found one species of wattle flowering in early May! It does make me wonder if this is not a biological response to Climate Change, because such early flowering is very unusual.

Whatever the reason for the incorrect scheduling, it is nice to wander the suburbs and appreciate the diversity and colour of the many species of wattle flowering at present. Australia has 950 indigenous species of Acacia out of a total of 1200, the remainder being native to parts of Africa. It’s therefore no surprise to find a wide range of forms, flower colours, leaf shapes and growth habits amongst this diverse group of plants.

Most Australians are familiar with Acacia pycnantha or the “Golden Wattle” which is Australia’s official floral emblem, but I want to tell you about a few different species that I like.

The first is A. willdenowiana, or the “Grass Wattle”. The common name of this Western Australian species is derived from its form, which is that of a sprawling shrub.  Acacia willdenowiana seldom grows more than 60cm in height, but can spread to more than a metre and a half wide. Like many species of wattle, this one has no leaves. Rather it uses modified leaf-stalks (called phyllodes) to perform the normal functions of a leaf. Because of the sprawling habit of this species, the bright yellow ball flowers of this are nearly sitting on the ground. With its grass-like apparance and bright flowers, the Grass Wattle is quite a curiosity.

Acacia willdenowiana grows low to the ground.

Another species that I really like is A. longifolia, which grows up to 10 metres in height. Native to the eastern states, this species has long rod-shaped inflorescences of pale yellow flowers which almost smother the tree. The branches weep slightly to give the tree a pendulant appearance and the canopy is dense, making sure that the flower display can be seen from a far distance.

Acacia longifolia provides a vivid display.

Finally, I reckon A. flexifolia is worth a mention. I spotted this species in full bloom today and it looked amazing. This species is from central New South Wales, and grows to a height of 1.5 metres. It has upright stems which blow in the breeze. When covered in vivid yellow blooms this plant is very eye-catching. Unfortunately, I seldom see this species grown in gardens which is quite a shame.

Acacia flexifolia.

Of course an article about wattles shouldn’t go without mention of A. leprosa ‘Scarlet Blaze’, but I’ve already discussed that species’ unique red flowers in a previous blog post. Yes, wattles now come in red!

Acacia leprosa ‘Scarlet Blaze’ has unique red flowers.

As you’re walking to and from work or school in coming days, please take a moment to look at the wattle trees that are flowering in your neighbourhood. Pay special attention to the shape of the leaves and the colour and form of the flowers. If you do, you’ll no doubt be amazed at the sheer diversity that this species has. From small ground-covers to massive trees, this genus really has something for everyone.

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Useful Website: If you find wattles to be of interest, I highly recommend the World Wide Wattle website which is jam-packed with useful wattle info. The site has descriptions of every Australian Acacia species as well as photographs and links to other relevant plant databases.

*Fortunately, I don’t suffer from hay fever

I am now reacquainting myself with the art after I purchased a macro lens last weekend – a Canon EFS 60mm f/2.8 Macro USM to be specific. And I am having a ball discovering the world at the micro level again.

For me, the macro lens is great because it allows me to capture the minute detail of plants that an ordinary 18-55mm lens is never going to capture. As someone who uses a microscope in his daily work, the macro lens is a nice ‘intermediate’ between the detail of a dissecting microscope and an ordinary camera lens.

Back in the days before digital photography, when I was a high school student, I used a Canon EOS 500N for all my photography. Of course I didn’t have the means to pay for a macro lens back then, so I settled for a Kenko tube extension kit. Sitting between the camera body and the standard 18-55mm lens, the effect was to increase the magnification capacity of the camera. It was a good substitute for a macro lens, and I used it frequently to capture the details of plants which was particularly useful during my horticultural studies at university.

Unfortunately, when I purchased my digital SLR, I discovered that the 350D used a slightly different lens attachment to the old camera and so my tube extension kit couldn’t be used any longer. Disappointed, I was determined that I’d buy a new macro lens. Eventually.

Having made the purchase, I am really happy with the Canon 60mm f/2.8 Macro. Such capacity for a high aperture really facilitates sharp photography at a level where the slightest shake will cause motion blur. Nevertheless, it decreases the depth-of-field considerably and so I am learning to adjust my photographic techniques to accommodate this.

The real challenge comes in using an appropriate aperture to increase the depth-of-field without reducing the light levels to make hand-held photography impossible. In some situations, a tripod just isn’t practical. Either way, it’s great fun and I am getting some great results.

Today I went to the Melbourne Conservatory in the Fitzroy Gardens to test out my macro photography. Of course the place was filled with other dSLR users trying to get photos, but I was able to focus on the small ferns, selaginellas and hydrangeas to get some special photos.

I’ll be working on my macro photographic technique in coming months, and of course will be posting to Flickr and Photologium.com.

Friends and family will be wondering what could possibly come next, after purchasing a macro and wide-angle lens? I reckon a fish-eye lens could be interesting….!

Picture details: 1. A marigold (Tagetes erecta cv.); 2. A Honey Bee pollinating a Sedum telephium ‘Autumn Joy’; 3. The flowers of a Hydrangea macrophylla.

It relates very much to the current debate about genetic engineering; specifically one of the ways in which we plant scientists transform (or genetically engineer) plants.

The story goes back to 1977 when plant scientist Mary-Dell Chilton and colleagues at the University of Washington made a revolutionary discovery; that “genetic engineering” actually occurred in nature (contrary to popular belief).

More specifically, Chilton demonstrated that Agrobacterium tumefaciens caused Crown Gall Disease in plants by incorporating a part of its own DNA (called T-DNA) into the genome of the host plant via a Ti plasmid. This genetic change caused the infected plant to produce nutrients for the bacterium.

Agrobacterium tumefaciens infecting a plant cell. Click on image for more details. (© Nature Publishing Group)

Fast forward to 2007, and A. tumefaciens is frequently used in laboratories to genetically manipulate plants.

The virulence part of the bacteria’s Ti plasmid – the portion that causes the gall disease – is substituted by scientists for a desirable trait such as drought or herbicide resistance. The plant is then deliberately infected with the bacterium and a new gene is inserted into the plant.

Yet despite the frequent use of A. tumefaciens in laboratories, no-one actually understood how it was that the bacterium could get its DNA into the plant’s nucleus and not be detected by the plant’s defences.

Infecting Plants

The steps towards infection by Agrobacterium have been known for years.

The Agrobacterium comes into contact with a plant cell, and a single-stranded copy of T-DNA is passed into the cell, along with virulence (vir) proteins. The VirD2 protein is attached to one end of the T-DNA and assists its passage into the cell. The bacterium also inserts the VirE2 protein into the target cell, and with the assistance of karyopherin α the T-DNA is transferred into the plant’s nucleus (where its DNA is kept).

What wasn’t previously understood is how it was possible for the T-DNA to be carried into the nucleus past all the plant’s defences.

Solving the Mystery

Armin Djamei and Heribert Hirt at the University of Vienna have shown how the A. tumefaciens bacterium tricks the plant’s defence system and why the plant’s own VIP1 protein was the key to solving the mystery of T-DNA insertion.

When a plant is infected with A. tumefaciens, MAPK genes are activated. These cause the phosphorylation of VIP1 and other defence-related proteins, allowing them to enter the nucleus.

The VirE2 protein which the Agrobacterium injected into the plant cell simply allows the T-DNA to bind to the VIP1 protein, enabling those foreign genes to infiltrate the nucleus undetected. Once the genes are inside the nucleus, they are incorporated into the genome.

So in effect, the T-DNA enters the plant cell nucleus by utilising VIP1 as a Trojan Horse!

This finding is significant because Agrobacterium-mediated transformation is the most common method for producing GM plants, and therefore its comprehension is beneficial to plant science and plant pathology.

This also shows that with good research and patience, even the most elusive of biological processes can be understood in due time. I think these biological discoveries are fascinating as we learn more and more about the world around us.

Scientific References:

Binns, A.N. (2002) T-DNA of Agrobacterium tumefaciens: 25 years and counting. Trends in Plant Science 7 (5): 231-233

Chilton, M.D. et al. (1977) Stable incorporation of plasmid DNA into higher plant cells: the molecular basis of crown gall tumorigenesis. Cell 11: 263–271.

Djamei, A. et al. (2007) Trojan Horse strategy in Agrobacterium transformation: Abusing MAPK defence signalling. Science 318 (5849): 453-456

Snow, A. (2003) Genetic engineering: Unnatural selection. Nature 424: 619

This story goes back to 2003 when the Commonwealth Government’s Office of the Gene Technology Regulator (OGTR) approved the cultivation of Bayer CropScience’s InVigor® and Monsanto’s Roundup Ready® herbicide-resistant canola (Brassica napus) for commercial oil production. In response, most Australian states (which have constitutional authority over agriculture) imposed 5-year moratoria on the basis that the economic and environmental risk was still unknown.

This was a sensible decision because it permitted more scientific and economic research to be conducted and for the community and farmers to express their concerns to government and industry.

GM canola has been grown in the United States and Canada since 1995. To date, there has been no evidence to suggest that there is a risk to the health of humans nor wildlife from growing such crops. In fact Bennett et al. (2004) found that growing a GM herbicide-tolerant crop would be less harmful to the environment and human health than growing the conventional crop, owing to the reduction of herbicide use. Indeed, there are many benefits that can come to Australia from the cultivation of GM crops.

Australia already cultivates GM cotton and carnations. The incorporation of genes for “drought resistance” in wheat and rice for instance could have dramatic environmental benefits, not least allowing us to grow more food with less water. The savings could be returned to our parched rivers and waterways.

Despite the potential benefits, there is a general paranoia amongst extremist environmental groups (such as Greenpeace) that GM-crops are somehow “unnatural” and “dangerous”. Such claims show a complete lack of scientific literacy. The labelling of GM crops as “Frankenfood” is a favourite scare-tactic amongst the environmental extremists.

A good example of the potential of GM was the FlavrSavr tomato, developed by Calgene. When tomatoes ripen, they become soft and are easily spoilt and so are picked green. The softening is caused by a protein called polygalacturonase, which is present in all tomatoes. Calgene scientists simply cloned the gene, flipped it backwards and re-inserted it back into the tomato. This antisense gene then blocked the function of polygalacturonase and the tomatoes stayed firm after ripening. No “foreign” genes were used, yet green groups went berserk and even suggested the tomatoes contained fish genes! (This claim was false).

Golden Rice provides another example of the positive potential of genetic modification. According to the World Health Organisation, dietary vitamin A deficiency (VAD) causes some 250,000 to 500,000 children to go blind each year. As a remedy to this problem, scientists Ingo Potrykus and Peter Beyer developed Golden Rice which contains elevated levels of β-carotene (provitamin A). Rice plants produce β-carotene in green tissues but not in the endosperm (the edible part of the seed). By addition of only two genes, phytoene synthase (psy) and phytoene desaturase (crt I), the pathway was reconstituted and β-carotene is consequently accumulated in the endosperm. The humanitarian benefit of cultivating this rice would be enormous, but for environmentalists objecting to the use of a “bacterial gene” in its development.

The notion that a “foreign” gene poses some risk to health or is unnatural is a myth. Aside from the lack of evidence of this process being dangerous in itself, gene transfer between bacteria and plants happens in nature, such as in the case of Agrobacterium tumefaciens. Sure, if a scientist were to transfer a gene encoding a toxin into an edible plant, that would be dangerous, but only because of the presence of toxin and not because the gene was “foreign”. Given that the DNA code is universal across all organisms and no genes have species-specific identifiers marking them as “plant”, “animal”, “bacterial” et cetera, this fear of the technology is misplaced.

One concern with growing GM canola is that herbicide-resistance genes will ‘contaminate’ non-GM canola crops via cross-pollination, since canola is an out-crossing species. In an Australian study, Rieger et al. (2002) found that canola pollen could be spread up to 3 kilometres away from source plants, but herbicide-resistance genes were present in an average of 0.03% of plants tested at those distances, suggesting that buffer zones could be successfully used where farmers want to grow non-GM canola without fear of contamination. This is especially applicable in the case of Tasmania. Under European standards for instance, “GM free” canola is permitted to contain up to 0.9% genetically modified material.

It is true that the organic sector could be affected by the commercial planting of GM canola, however ABARE currently estimates that organic canola accounts for less than 1% of the Australian canola crop. In any case, the economic debate is one which farmers will need to have and decide upon. This is not an environmental risk, but an economic one.

I believe that the adoption or otherwise of GM crops should be conducted where it is economically and environmentally prudent to do so. If a particular agricultural industry doesn’t want to grow GM crops because they feel their industry can gain higher prices with non-GM, then I support them wholehartedly. But if the environmental return (eg less use of herbicides, less water use etc) and the economic return is greater with GM crops, then as a society we should embrace the technology.

Of course there are risks. One risk is of GM crops hybridising with wild relatives in species where this is possible and wild relatives are present, causing a transfer of new traits (such as herbicide resistance) to these plants. However it is the job of the OGTR to evaluate and regulate new releases and to date, they’ve done an excellent job in risk assessment. Anyone who works in a PC2 laboratory would know how stringent the Gene Technology Act 2000 is.

It is up to affected farming groups, the OGTR, the Food Standards Authority and state governments to decide for each agricultural sector what is best for consumers, industry and the country. Consumers are entitled to stringent labelling regulations on all food, and the choice whether to purchase GM food products.

Genetic modification of crops offers Australia many opportunities and it would be foolish in the extreme to ignore the potential of this tried-and-tested technology and miss out on what it can offer the people of Australia and the world.

Scientific references:

Bennett et al. (2004) Environmental and human health impacts of growing genetically modified herbicide-tolerant sugar beet: a life-cycle assessment. Plant Biotechnology Journal 2: 273–278

DallaPenna et al. (1986) Molecular cloning of tomato fruit polygalacturonase: Analysis of polygalacturonase mRNA levels during ripening. Proceedings of the National Academy of Science USA 83 (17): 6420-6424

Rieger et al. (2002) Pollen-Mediated movement of herbicide resistance between commercial canola fields. Science 296 (5577): 2386-2388

Image credits:

1. Canola field by Neal Sanche, used under a Creative Commons licence.

2. Canola plant by Richard Rosalion, used under a Creative Commons licence.