November  2014  

 

WIN  Christmas  Gathering  

Saturday  6th  December,  2014     at  the  property  of  Gordon  and  Carol  Meiklejohn   25  Wild  Oaks  Road,    Belimbla  Park  (The  Oaks).  2570   Phone:  4657  1912    

This  is  a  BBQ  lunch  and  Farm  walk.  Arrive  11.30am    

12.30pm:  –  Christmas  Lunch    -­‐  BBQ  provided.  Members  are  asked  to  bring  a  salad  dish   or  dessert,  and  own  drinks.    RSVP  -­‐  Please  contact  Carol  on  4657  1912  by  Monday,   1/12/14  to  confirm  attendance  catering  details.   2.30pm:  -­‐  Farm  Walk    

 

2014  Committee President:  Peter  Stewart     Vice  President:  Gordon  Meiklejohn     Secretary:  Frank  Allatt     Treasurer:  Gavin  Bottomley     Committee:  Paul  Nixon,  Brian  Parry,  David  Robinson,  Sue  Stewart.  

2014  Waratah  Season   Craig  Scott  from  East  Coast  Wildflowers   reports  that  relative  to  the  past  few  years  the   2014  waratah  season  started  later,  but   continued  for  a  longer  period  of  time.  Market   volume  was  down  and  there  was  no  sudden   big  flush.  Bloom  quality  was  good,  although   towards  the  end  some  product  went  “soft”  and   had  to  be  recut  –  possibly  because  the  product   had  been  held  in  cool  store  for  a  number  of   days  and  not  recut  before  being  sent  to   market.  Prices  paid  for  blooms  were  mostly  a   little  higher  than  for  2013.  This  season  there   were  fewer  pinks  available  for  sale.  However,   there  were  a  significant  number  of  bunches,   mostly  with  short  stems,  with  many  of  the  bunches  being  whites.       Comment  -­‐  Possibly  the  short  stems  reflect  the  extremely  dry  2013  Spring  and   summer.    Spring  is  when  plants  are  fertilised  and  when  water  (preferably  rain)  is   needed  for  new  and  adequate  stem  growth    to  occur  –  both  for  stem  length  and   for  stem  diameter.  At  my  place  there  was  little  rain  until  well  into  February  

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  2014,  long  after  the  period  of  vigorous  plant  growth,  and  also    after  bud  set   would  normally  occur.  Frank    

August  2014  Farm  Visits    On  Saturday  9th  August,  a  fine  and  sunny   winter’s  day,  a  large  number  of  growers  and   florists  gathered  in  the  morning  at  the  East   Coast  Wildflowers  property  of  Craig  and   Angie  Scott  at  Mangrove  Mountain  and  in   the  afternoon  at  the  property  of  Barry  and   Robert  Luff.  At  lunch  time  there  was  an   address  by  Rick  Donnan  on  the  principles  of   hydroponics  and  how  hydroponics  may   relate  to  the  flower  industry.  There  was  also   a  brief  WIN  meeting.  Florists  were  extended   a  special  welcome.  Growers  were  from  the   mid-­‐north  coast,  central  coast  and  the  Sydney/  Blue  Mountains  areas.   Both  properties  have  large  commercial  plantations  with  numerous  varieties  of   native  plants  grown  for  flowers  and  foliage,  both  in  the  field  and  under  shade.  As   the  visit  was  close  to  spring  and  many   plant  varieties  were  ready  or  almost  ready   for  harvest,  the  WOW  factor  was  great  for   both  growers  and  florists.    The  everlasting   daisies  (Bracteantha  ?)  and  their  many   colours  bred  and  grown  by  Robert  were  of   particular  interest  as  were  the  ptilotus  ?  (a   desert  plant)  grown  under  shade  by  Craig.       Many  thanks  to  both  Craig,  Barry  and   Robert  for  making  their  properties   available  and  sharing  their  experiences   with  us.  

  Waratah  Flowering  Project  Update   The  2014  exercise  set  out  to  confirm  the  trial  results  from  2013  and  to  improve   on  the  product  results.     Robyn  reports  that  they  have  confirmed  that  they  can  switch  buds  from  veg  to   floral  and  that  depending  on  when  we  treat  and  the  cultivar,  they  flower  from  1-­‐ 2-­‐3  weeks  later  and  maybe  up  to  4  (when  we  get  the  stringers  late  flower  data   in).   So  we  can  potentially  increase  the  %  of  flowers  on  a  plant  and  have  it  flower   later.    This  year  all  flowers  were  complete.  Some  had  more  whorls  of  bracts   e.g.    Starfire  and  Brimstone  Passion,  which  looked  attractive  according  to   Gordon.  We  have  also  narrowed  the  treatment  concentration  so  now  it  is  just   timing  that  we  need  to  work  on.   Robyn  said,  “I  have  spoken  to  RIRDC  and  they  are  not  looking  to  fund  wildflower   projects  beyond  what  they  have  on  the  books  at  present.  (RIRDC  has  been   2  

  restructured.)  HIAL  funding  is  a  possible  option  and  I  will  call  the  manager  to  see   what  the  possibilities  are.  It  may  be  that  we  will  again  need  a  Voluntary   Contribution    from  growers  to  match  HAL  funding,  in  which  case  an   indication/pledge  from  growers  will  be  required.”   The  Australian  Government  has  welcomed  the  registration  of  Horticulture   Innovation  Australia  Limited  (HIAL)  as  a  new  research,  development  and   marketing  body  to  support  Australia’s  $9.5  billion  horticulture  industry.  The   establishment  of  the  new  entity  follows  a  recent  independent  report  into  the   performance  of  Horticulture  Australia  Limited  which  recommended  a  change  to  a   new,  grower-­‐owned  research  and  development  company.  October  8th,  2014.  

  For  recent  RIRDC  Wildflower  Publications.  Go  to  http://www.rirdc.gov.au  and   under  publications  scroll  down  to  Wildflowers.        

Introduction  to  hydroponics   By  Rick  Donnan   Definition   Hydroponics  is  more  usually  known  in   most  of  the  world  as  soilless  culture.  It  is   the  growing  of  crops  in  systems  isolated   from  the  soil,  with  or  without  a  medium,   where  all  the  plants’  water  and  nutrient   requirements  are  supplied  by  a  nutrient   solution.   The  difference  to  pot  plants,  which  often   use  soilless  potting  mixes,  is  that   hydroponics  applies  to  cropping  and   uses  only  nutrient  solutions  and  not  slow   release  fertilisers.   Systems     There  are  two  major  splits  between  the  different  hydroponic  systems.  The  first  is   whether  they  recirculate  (closed  system)  or  operate  by  ‘free  drainage’  (open  system).   The  second  split  is  whether  they  use  a  growing  medium  to  contain  all  the  roots,  or  are  a   water  based  system.     The  basic  requirements  of  a  hydroponic  system  are  that  it  must  supply  the  plant  roots   with:   • Adequate  water   •

Adequate  oxygen  

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Adequate  balanced  nutrients  

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Sufficient  void  space  for  the  mature  plant’s  roots  

Water  based  systems     The  major  water  based  systems  are  flood  and  drain  (also  called  ‘ebb  and  flow’),  nutrient   film  technique  (‘NFT’),  tank  systems  and  aeroponics.    

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  Flood  and  drain  is  rarely  used  for  cropping,  but  it  is  sometimes  used  for  growing  on   propagated  plants,  such  as  tomatoes,  to  an  advanced  stage  before  planting  out  into  the   main  system.     NFT  is  a  well  publicised  system.  It  uses  channels  down  which  a  thin  film  of  nutrient   solution  flows,  to  be  collected  in  a  sump  and  returned  as  continuous  flow.  Other  than  for   some  tomato  cropping,  it  is  mainly  used  for  short  term  crops  such  as  lettuce.  Of  interest   is  that  Australia  has  by  far  the  largest  area  of  NFT  in  the  world.  We  typically  use  100  mm   wide  by  50  mm  high  channels,  grouped  on  tables,  to  grow  lettuce,  herbs  and  more   recently  Asian  greens.     Aeroponics,  the  misting  of  nutrient  solution  onto  plant  roots,  also  gets  publicity.   However,  it  is  used  commercially  to  only  a  very  limited  extent  for  short  term  crops.  It  is   obviously  very  vulnerable  to  pump  failure.  There  are  a  number  of  tank  type  systems   using  deep  containers,  usually  with  beds  or  floats  on  top  to  hold  the  plants.  Their  design   must  ensure  adequate  aeration  of  the  nutrient  solution.  Commercially  they  are  also  rare,   and  normally  used  only  for  short  term  crops.       By  their  nature,  all  water  based  systems  are  closed.  Combined,  they  account  for  no  more   than  5%  of  the  world’s  hydroponic  area.   Media  based  systems   The  bulk  of  hydroponic  systems  use  media  in  containers.  There  are  a  few  different  styles   of  container  used,  from  simple  boxes  and  pots  to  open  topped  flexible  plastic  bags.  The   most  popular  are  lay  flat  ‘pillow’  bags,  which  have  the  advantage  of  reducing   evaporation  from  the  bag.   There  are  a  wide  range  of  media  used.  Worldwide,  the  most  common  are  rockwool  and   cocopeat,  which  would  be  used  in  over  80%  of  the  world’s  hydroponic  area,  leaving   about  15%  to  cover  all  other  media  combined.     In  general  the  media  used  reflect  price  and  local  availability.  Apart  from  rockwool,  there   is  a  range  of  inorganic  media  such  as  perlite,  sand,  scoria,  pumice,  and  gravel.   Vermiculite  was  a  media  promoted  in  the  1950’s,  but  is  now  only  used  in  mixes.   Expanded  clay  is  used  occasionally,  it  is  relatively  expensive  and  mostly  mostly  used  in   hydroculture,  that  is,  for  indoor  plants.  Apart  from  cocopeat,  other  organic  media   include  peat,  sawdust,  bark,  and  a  number  of  proprietary  wood  based  and  artificial  foam   products.   Media  based  systems  are  all  dripper  fed,  usually  with  a  run-­‐off  of  about  30%.  In  open   systems,  this  is  hopefully  used  responsibly  elsewhere,  such  as  on  another  crop  or   pasture.  In  closed  systems,  the  run-­‐off  is  recovered,  usually  disinfected,  and  returned  for   reuse.     Raw  water   For  hydroponics  it  is  essential  that  you  have  a  reliable  and  adequate  volume  of  water   supply.  Its  quality  is  especially  important.     The  water  needs  to  have  relatively  low  dissolved  solids,  no  higher  than  EC  0.5  mS/cm   and    preferably  no  higher  than  0.3,  especially  if  it  contains  mainly  sodium  chloride.   Freedom  from  solids  (which  can  block  drippers)  and  pathogens  (which  can  infect  all   your  plants)  are  both  very  important.    Town  water  supplies    are  usually  OK  (except  if   you  live  in  Adelaide,  for  example).   However,  beware  if  you  use  dam  water.  Solids  may  need  to  be  removed  with  a  good   sand  filter  and  there  is  a  strong  possibility  of  dangerous  pathogens  being  present.  In  this   case  it  is  essential  to  sterilise  the  water  before  use  in  hydroponics.  The  simplest  method   of  sterilising  is  to  use  granular  pool  chlorine  (calcium  hypochlorite).  Dose  at  20  parts   per  million  and  leave  standing  for  a  day.  The  hypochlorite  needs  to  be  deactivated   before  the  water  is  used.  Deactivate  by  aeration  (spraying)  and  time.    

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  Management   The  first  vital  aspect  for  a  beginner  to  hydroponics  is  to  ensure  that  you  use  a   hydroponic  nutrient.  This  must  contain  all  the  macro  and  micro  nutrients.  In  particular,   beware  of  the  so  called  ‘complete  fertilisers’,  such  as  Aquasol,  that  some  of  you  may  be   using.  These  are  not  complete  –  they  are  wide  range  supplements  intended  for  growing   in  soil,  but  usually  lack  adequate  calcium  and  magnesium,  and  include  unacceptable   levels  of  urea  and  ammonium.   If  using  concentrate  solutions  (typically  100  to  1)  for  ease  of  management,  they  must  be   split  into  two  parts,  normally  called  ‘A’  and  ‘B’.  This  is  because  at  these  high   concentrations,  calcium  phosphate  and  sulphate  and  possibly  iron  will  precipitate.   Therefore,  Part  A  normally  contains  the  calcium  nitrate  and  iron  chelate,  and  everything   else  goes  into  Part  B.     The  essential  basis  of  management  is  to  monitor  and  control  the  root  zone  solution.   Growers  often  get  obsessed  with  the  feed,  but  this  is  only  the  means  to  managing  the   root  zone.  With  most  media  it  is  impossible  to  get  a  solution  sample  direct  from  the  root   zone,  so  the  best  practical  sample  is  the  run-­‐off  solution.     Management  is  based  around  sampling,  measuring  and  recording  the  analysis  of  the   feed  and  root  zone  solutions.  Daily  measurements  should  be  electrical  conductivity  (EC),   pH  and,  for  media  systems,  the  percentage  of  the  feed  which  is  run  off.  Occasional  full   nutrient  analysis  of  the  run-­‐off  solution  is  needed  for  good  control,  especially  if   recirculating.   In  media  systems,  the  irrigation  system  must  be  adequate.  The  plants’  water  demand  is   mainly  in  response  to  transpiration,  the  main  driver  of  which  is  radiation.  The  irrigation   system  must  be  able  to  replace  this  water  taken  up  by  the  plant,  especially  during  the   peak  of  the  day.   Because  relatively  more  water  than  nutrient  is  taken  up,  especially  in  summer,  there  is  a   rise  in  EC  between  feed  and  run-­‐off  and  this  needs  to  be  managed.  pH  also  needs  to  be   managed,  although  it  is  not  as  critically  important  as  indicated  in  many  hydroponic   books.  If  you  use  a  more  stable  form  of  iron  chelate,  such  as  DTPA  or  EDDHA,  then  pH   from  5.5  to  6.5  is  good,  with  periods  of  out  to  5.0  to  7.0.       One  design  aspect  particularly  impacts  upon  management.  This  is  the  volume  of  nutrient   solution  per  plant.  The  lower  the  volume,  the  less  the  cost  of  media  (or  tanks  for  water   based  systems)  However,  there  is  a  compromise  here.  The  lower  the  volume  per  plant,   the  faster  and  more  severe  any  swings  in  root  solution  EC,  temperature,  nutrient   imbalance,  and  possibly  pH.   Benefits   One  major  reason  for  converting  to  hydroponics  is  problems  with  root  disease.   Hydroponics  enables  the  root  zone  to  be  optimised  for  the  uptake  of  the  nutrients  the   plant  requires.  If  what  you  need  are  healthy,  vigorous  plants,  hydroponics  is  well  worth   considering.  Especially  when  compared  to  soil  growing,  better  yields  can  be  obtained   with  the  use  of  significantly  less  water.   Some  hydroponic  books  promote  the  idea  of  ‘total  control  of  the  plant’  –  this  is   nonsense.  The  scope  to  manipulate  the  plant  by  adjusting  the  nutrient  balance  is  limited.   However,  there  is  some  potential  to  influence  plants  by  adjusting  the  strength  of  the   root  zone  solution.  The  weaker  is  this  solution,  the  softer  the  plant.  Conversely,  the   stronger  the  root  zone  solution,  the  harder  the  plant.  Other  means  of  manipulation  are   the  well  known  ones  related  to  the  environment,  rather  than  hydroponics,  such  as   temperature  and  day  length.  Where  legal,  plant  growth  regulators  can  be  useful.   For  minimum  vulnerability  I  would  recommend  using  a  media  based  system,  set  up  with   a  reasonable  volume  per  plant.  At  least  initially,  it  is  easier  to  manage  if  operated  as  free   drainage.  This  makes  nutrient  management  much  easier,  because  the  nutrient  solution  

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  is  run  off  before  it  gets  too  far  out  of  balance.  With  more  experience  the  system  could  be   closed  and  the  run-­‐off  recirculated.     Rick  Donnan  was  the  inaugural  President  of  the  Hydroponics  Association  of  Australia  and  is   in  demand  as  a  speaker  by  the  Industry  both  here  in  Australia  and  Abroad.  For  more   information/articles  on  hydroponics  go  to  http://www.hydroponics.com.au  .Rick  spoke  at   the  August  2014  WIN  Meeting  and  has  an  current  article  on  the  hydroponics    site.    

 

   

The  basics  of  pesticide  resistance   Professor  Raymond  Cloyd  is  a  research  and  extension  specialist  based  at  Kansas  State  University,  working  in   the  areas  of  integrated  pest  management,  plant  protection,  horticultural  cropping  systems,  pesticides  and   insect-­‐plant  interactions.  This  is  an  extract  from  the  Professor  Cloyd  paper  on  pesticide  resistance,  that  was   reprinted  in  Issue  44  September  2014  of  the  magazine  Australian  Flower  Industry   www.australianflowerindustry.com.au”.  Pesticide  resistance  is  an  important  issue  for  all  flower  growers   who  use  chemical  products  to  manage  crop  pests.  

What  is  resistence?   Resistance  is  an  inherited  trait.  When  a  pest  population  is  exposed  to  a  pesticide,  genetic  variability   in  the  pest  population  permits  the  survival  of  some  of  the  individuals.       How  does  resistence  develop?   After  frequent  applications  of  a  given  insecticide  over  multiple  generations,  susceptible  individuals   are  removed  from  the  population  and  resistant  individuals  remain  to  breed  and  reproduce.   What  influences  the  rate  of  resistance  development?  The  rapid  development  of  resistance  is   mostly  due  to  two  biological  factors:  short  generation  time  and  high  female  reproduction.   Other  factors  that  may  influence  the  rate  of  resistance  developing  in  insect  pest  populations  can   be  divided  into  operational  factors,  which  are  under  the  control  of  producers,  and  biological   factors  that  are  intrinsic  to  the  insect  pest  population.   Operational  factors  include:   length  of  exposure  to  a  single  insecticide,   frequency  of  insecticide  applications,     dosage  (use  rate)  of  insecticide  applied   uniformity  of  the  spray  coverage  

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  proportion  of  the  insect  pest  population  killed   timing  of  insecticide  application  and  the  susceptibility  of  the  pest  life  stage(s)   previous  history  of  insecticide  use  and  relatedness  of  an  insecticide  to  those  that  have   previously  been  applied   presence  or  absence  of  refuge  sites  or  hiding  places.   Biological  factors  include:   time  to  complete  one  generation  (egg  to  adult)  number  of  offspring  produced  per   generation  insect  pest  mobility   plant  host  range   genetic  system  of  the  pest  and  genetic  expression  of  the  resistance  trait.   Greenhouse  conditions  can  increase  the  rate  of  resistance  development.  The  temperature  and   relative  humidity  are  typically  conducive  for  rapid  insect  pest  development  and  reproduction.   I  n  addition,  the  greenhouse  environment  tends  to  prevent  pesticide-­‐susceptible  individuals  from   entering  and  breeding  with  resistant  insect  pests.  Biological  control  agents  or  natural  enemies   such  as  parasitoids  and  predators  are  often  absent,  or  present  at  low  numbers,  and  may  not  be   able  to  immigrate  into  greenhouses.  Finally,  intensive  year-­‐round  production  in  many   greenhouses  provides  a  continuous  food  supply  for  insect  pests,  often  resulting  in  multiple   generations  per  year  and  frequent  exposure  to  insecticide  applications.   How  can  resistance  be  avoided?   Resistance  management  is  designed  to  preserve  the  effectiveness  of  currently  existing   insecticides.  This  primarily  involves  the  judicious  selection  and  accurate  application  of   insecticides,  and  integrating  them  with  other  plant  protection  strategies  consistent  with  a   basic  pest  management  philosophy.   Below   are   some   general   guidelines   to   help   minimise   the   likelihood   of   a   pest   population   developing  resistance  to  any  insecticide.   Monitor   crops   regularly   to   appropriately   time   applications   of   insecticides,   in   order   to   target   the  most  susceptible  life  stage  of  the  pest.   Implement  proper  cultural  (water  and  fertility)  and  sanitation  (weed  and  plant  debris   removal)  practices.   If  feasible,  screen  greenhouse  openings  so  as  to  prevent  entry  of  insect  pests.   Implement  the  use  of  biological  control  agents  or  natural  enemies.   Use  synergists  when  applying  insecticides  to  inhibit  enzymes  involved  in  detoxification   (however,  it  is  important  to  read  the  label  to  determine  whether  a  synergist  has   already  been  incorporated  into  the  formulation).   Rotate  insecticides  with  different  modes  of  action.   Use  insecticides  with  broad  modes  of  activity  such  as  insect  growth  regulators,  insecticidal   soap  (potassium  salts  of  fatty  acids),  horticultural  oils  (petroleum  and  neem-­‐  based),   selective  feeding  blockers,  beneficial  bacteria  and  fungi,  and  microorganisms.   "It  is  important  to  understand  resistance  and  to  be  aware  of  all  the  factors  that  can  enhance   its  development  in  pest  populations."     Dr.  Raymond  A.  Cloyd,  Ph.D.  is  a  Professor  and  Extension  Specialist  in  Horticultural  Entomology/Integrated  Pest   Management  at  Kansas  State  University.  Dr.  Cloyd's  research  interests  are  associated  with  pest   management/plant  protection,  biological  control,  plant-­‐insect  interactions,  and  non-­‐chemical  means  of  dealing   with  insect  and  mite  pests.  

More  information  on  resistance  management  can  be  found  at   http.//www.ksre.ksu.edu/bookstore/pubs/mf2905.pdf  

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Related  Government  Services   For  registered  chemical  products,  go  to  Australian  Pesticides  and  Veterinary   Medicines  Authority  web  site  http://www.apvma.gov.au   Infopest  is  a  free  and  online  comprehensive  agricultural  and  veterinary   chemicals  data  base  managed  and  maintained  by  Growcom  as  a  service  to   agriculture  throughout  Australia.  Infopest  is  accessed  by  going  to   http://www.infopest.com.au  

New  Electronic  Tool  to  Identify  Pests   Although  developed  for  the  nursery  industry,  the  Pest  Identification  Tool  provides  users   with  information  to  help  in  identifying  and  treating  insect  pests,  disease,  disorders  and   weeds.  The  tool  is  electronic  and  portable  with  a  design  to  allow  viewing  on  a  computer,   smart  phone  or  tablet.  There  is  advice  on  diagnosing  diseases,  integrated  pest   management,  beneficial  insects,  insect  pest  lifecycles,  and  plant  disorders.  The  tool  was   developed  in  Queensland.  For  more  information  go  to  http://www.pestid.com.au  .    

   

 

Merry Christmas and a Happy and Prosperous 2015 to all.   This  Newsletter  was  prepared  by  F.  Allatt.   Contact:    ph:  0245672093.  E:  [email protected]  

 

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