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Plantation BasicsGeneral requirements for Eastern Australian Cutflowers
Drainage testdig holes around 30-60cm deep, fill
with water. If water has drained away in 6 hours or less, you have reasonable drainage.
Normal preparation and raised beds should work. If water has not drained, you have a
problem. You can improve drainage by installing slotted pipe drains and / or adding
material like coarse sand, gravel, bark & hardwood chips. However the volume added
needs to be considerable, more than 30cm deep over the bed area. Soil testForm a ball of moist soil in your hand, then squash it. Does it crumble (friable) or stick together (clay). Clay can be treated with gypsum, and most soils will benefit from increased levels of organic matter from biodegradable mulchs or green manure crops. A professional soil test can be
useful if the analyst has experience with Australian plants' physical & nutritional
requirements. Test results should include quantitative results to allow
comparison with other growers and seasons. Leaf testLeaf sample testing can provide more
precise information on what the crop has actually taken up from the soil, and so
can be a valuable guide for fertiliser programs. Many Eastern Australian crops
are relatively new to cultivation, so there are no long term reference levels
for leaf testing. Compare your results with other growers and your own previous
results; try to correlate with observation of crop performance. Nematode test (nematodes are deadly to many Riceflowers)Lab tests are available but
expensive & complex. Take soil samples, at least 6 - 8 from over the whole area. Break
up finely and mix thoroughly. Place soil in pots (washed with bleach) on a bench out of
contact with the ground. Sow tomato seeds. When the tomato plants are around 5 -
10 weeks
old, remove from pots and carefully wash soil off roots. Examine roots for abnormalities
like lumps or galls, which probably indicate the presence of nematodes. Water supplyDrip irrigation is usually used for its low cost and water use efficiency. A drip rate of 4 litres per hour is common for flower crops. Dripper spacing depends on soil type, more porous soils need closer spacings. Use a good filter. How often and how much water to use can only be determined by observation and experience for each crop and site, depending on exposure, weather, soil, plant age, water use and growth stage. On our shallow rocky podsolic loam in a very dry year (50cm rainfall) we would allow 4 ML /ha on 6 year old Christmas Bush, a crop that needs plenty of water. A normal year (125cm rainfall) would need much less, as would a crop like Riceflower which uses much less. A sandy soil or exposed location would need more water. Have your supply tested because your
fertiliser program depends on the base level of mineral salts in your water. Shade cropsLight shade (30%) cloth is similar to an open forest habitat, and will provide some heat and wind protection with still sufficient light for winter growth Blandfordia : flowers need protection from heat, wind and birds. Removable shade could be used for the flowering season. Alloxylon pinnatum : a rainforest tree, only flowering where it emerges into the sun. May benefit from a cool aspect. Rainforest foliage crops, like Lomatia and Stenocarpus, need some protection to keep the long-lived leaves in prime condition and colour. Crowea 'Festival' : does
not like hot soil, will benefit from a cool aspect. MulchesOrganics such as hay, straw, other crop residues like tea tree mulch, cotton trash & bagasse, softwood chips and sawdust are often cheap to buy but can be expensive in labour to apply. Good for soil life over time but not always as good at weed suppression. Need to be redone every 1 - 2 years as they break down. Beware weed seed and too small particle size. Particle size influences both soil aeration and microbial interaction. Small particle sizes break down much quicker and may cause nitrogen depletion. Hardwood chips are quite inert and do not break down quickly, providing good weed control. Phenols leeching from hardwood do not seem to be a problem for most native crops, but vary in different timbers, and may have caused problems with some crops. Trial first. Weed mat is more expensive upfront but is quick to install and long lasting; does the best job on weed suppression especially in the early years of plantation establishment. There may be trade-off between weed
suppression and soil nutrition. Weed control.Weed control is a major expense in maintaining a plantation. Weed control can't be ignored because weeds rob crops of water and fertiliser and also host many pests and diseases. Weeds can cause total crop loss in early establishment and severe reductions in yield later. Most growers need to use all available control methods at times, eg mulching, spraying, mowing, slashing, brushcutting and hand-weeding. Systemic herbicides may be transferred to crops by root contact, especially with perennial grass roots, in some circumstances, with deadly results. Contact herbicides may be safer for the crop but not as effective in control; they may also be more dangerous to the user. Always use herbicides cautiously and follow the label directions. Spray with large controllable droplets only when conditions are suitable. Thorough weed control before planting is easier and safer than later.
FrostsGrowers have prevented frost damage on
susceptible crops (especially Christmas Bush) at around - 4°C by spraying Envy™, a polymer
anti-transpirant that apparently inhibits the ice
nucleating bacteria. The product degrades in around 5-6 weeks, so two or more sprays are
used each winter. It seems to give several extra degrees of protection. WindYou won't pick high quality flowers from a windy site. Some air movement is beneficial to dry foliage and flowers but crops subjected to frequent strong winds will not look as good and have shorter stems and less vaselife. Plant a windbreak of hardy local species, preferably before planting your
crop. Get local advice on species. Casuarina has been a top performer in
windbreaks in NSW. you can also build an instant break with cloth, but it needs
to be properly designed to take the load. LayoutMounded rows provide insurance against plant death from over-wet roots in the exceptionally wet periods common in NE Australia. We recommend mounding in all soils except sands, rocks permitting. Often higher mounds give better growth, because of increased aeration in the root zone. But higher mounds may dry out more in dry times. Mounding on a true contour line can result in water ponding on the high side, so put some fall in the line. Row layout is affected by land shape, slope, boundaries, access and soil. Often rows are best oriented somewhere between a true contour and directly downhill. Consider erosion risk on steep slopes. Allow enough space between rows for wheeled vehicle access for spraying and
harvesting when crops reach mature size. Allow room to turn around at row ends.
Put in cross roads around every 50m, even if rows continue. This speeds
operations later.
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