Royal Botanic Gardens Victoria Annual Report 2018-19

COMPLETING CRANBOURNE
Significant progress has been made
to improve access to the Cranbourne
Gardens. Royal Botanic Gardens Victoria
has provided significant design and
technical input to the City of Casey
concerning a major roundabout treatment
on the South Gippsland Highway. This
roundabout will serve as a ‘gateway’ to
the Cranbourne Gardens and importantly
increase awareness of the Gardens to
passing traffic.
To improve road quality to the western
entrance, partial sealing of Ballarto Road
has been undertaken. Royal Botanic
Gardens Victoria and City of Casey have
allocated funds for its completion due
later in 2019.
Infrastructure Management
Major Infrastructure management projects
have been undertaken at Cranbourne
Gardens including extensive road and
path repairs.
An asphalt overlay has replaced 850 m2
of badly damaged road along Stringybark
Drive. Two sections of Philip Moors
Drive, a total of 4,840 m2, were resealed
leaving the area from the front gate to
Stringybark Drive to be completed (3,800
m2).
Australian Garden Path upgrade
Five areas of path within the Australian
Garden were upgraded to concrete
walkways. These included: front of the
Visitor Centre, Bus Stop 1, Source Pool
Path, Diversity Garden and the Water
Saving Garden. A total of over 790 m2 of
path was upgraded.
An ageing and unsafe viewing platform
in the conservation zone was removed
and replaced with a new recycled plastic
platform, which has made this area safer
for wildlife. The Box Garden Bridge in the
Australian Garden was reinforced and
timbers were replaced with sustainable
Australian hardwood.
Landscapes
Cranbourne Gardens engaged Perry
Lethlean from Australian landscape
architecture company TCL to review
specific Australian Garden precincts.
The review identified that the majority
of the Australian Garden precincts
were performing well against design,
horticultural and visitor objectives.
Consequently, the focus has shifted to
review The Ian Potter Lakeside Precinct,
Stringybark Garden and Arid Garden.
A detailed design has been completed
to replace the use of potable water
with recycled water (from the Eastern
Treatment Plant at Carrum Downs)
to irrigate the Australian Garden.
Construction of project infrastructure is
expected to be completed at the end of
the 2019–20 financial year.
Ecological Management
The installation of 30 hectares of
ecological fencing through selected areas
of the conservation zone has commenced
and is due for completion in late 2019. The
aim of the ecological fencing is to manage
the effects of native mammal browsing
on indigenous vegetation and encourage
natural regeneration. A detailed
assessment to mitigate biodiversity
threats and impacts of vehicle traffic and
wildlife has been completed. Initiatives
and works will commence in 2019–20.
Enhancing the Australian Garden
The Red Sand Garden renovation was
completed. Works included the complete
replacement of soil in the north line and
circle beds, replacement of mulches, regrooming
the Red Sand Garden surface
and re-colouring the lunettes. Planting
occurred with support received from
Cranbourne Friends, Chisholm students
and Garden Ambassador volunteers.
Cranbourne Masterplan
The Cranbourne Gardens Masterplan
identifies opportunities to place an
increased emphasis on the utilisation,
conservation and display of a range
of south-eastern mainland Australian
flora within the Australian Garden living
collections. The number of southeastern
Australian taxa in the Australian
Garden collections has increased with
the addition of over 200 species of wild
collected plants. Field collections were
taken at sites including the Grampians,
Anglesea Heathlands, Ironbark Basin,
Mt Hotham (and the alps more
generally), Mt Baw, Mt Buffalo,
Feathertop, Wyperfeld, Hattah Lakes,
Calperum Station, Ned’s Corner Station
and a number of smaller reserves in
north-west Victoria.
The development of Curatorial
Management Plans (CMPs) for each
precinct in the Australian Garden
took a multi-disciplinary approach to
plant selection incorporating design,
organisational, educational, interpretive,
horticultural, conservation and research
objectives for the Australian Garden.
The Australian Garden was established
on the footprint of a former sand
extraction site, consisting of highly
modified and highly variable subsurface
sands, causing growing issues in
some areas. Consequently, Cranbourne
Gardens has implemented a program
of site inspections to improve acidity,
organic matter, nutrient levels, and water
management. In trial treatment areas, soil
organic matter has been incorporated and
soils have been treated with agricultural
lime to address pH concerns. Across
the garden, organic mulches have been
changed to a much courser material.
Initial results have shown improvement to
the soil.
Interpretation Master Plans are currently
in early stage development for both
Melbourne and Cranbourne Gardens.
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