Crop management tips
FRW: Proper FRW controls are essential. Skirting programs need to be conducted as fruit weigh down branches.
Fruit fly baiting: Prepare the spray rig and chemicals to intensify your baiting program
Preparing for autumn:Prepare for the copper spray program and snail bait application for March.
Nutrition: Sites with a low crop load are a risk of coarse rind texture. Some growers are applying MAP to try and help smooth out rinds, however there is no research to indicate if an application this late provides benefit. Low crop loads blocks should have a lower than average nitrogen and potassium application.
Drier and warmer than average conditions are expected for March through to May. This might hasten the internal maturity of fruit. A series of days above 40oC was experienced in January and the first half of February. This increased average maximum and minimum temperate by 1 to 3oC. Very dry conditions have been experienced and irrigation application volumes is expected to be above average
Crop status and management
All varieties are at the cell expansion stage. Following are some comments on crop load based on anecdotal feedback, the official citrus Australia crop estimate reports should be available in March. The Riverina will probably have a significantly below average crop whilst the Sunraysia will probably be below average and similar to the 2016 crop. The Riverland will probably have crop loads similar to last season (below average to average). The imperial mandarin crop is significantly below average throughout the regions. The crop loads are very variable for the Riverland and Sunraysia, some blocks have low crop loads and some are above average.
Pests, diseases and weeds
Scales: The hot weather over January and February would have increased the mortality of young scales, however it would have also increased the mortality of scale predators and parasites. Blocks that have had previous interventions (e.g. Samuari®, Confidor®, Movento®, oil etc.) and with low levels of scale populations should be safe, however blocks that have a reasonable population of scale, especially in the inner canopy are at risk of a late generation infestation. Check your block carefully (especially the inner canopy).
Cottony cushion: Now is a high-risk period as crawlers are starting to be on the move. They can easily cause a late season infestation and sooty mould issues. Parrafinic oil sprays can provide good control and if oil is too late chemical options are available.
Fullers Rose weevil: Detections of weevil have been higher than usual and growers must be extra vigilant to ensure all controls are applied and monitor carefully.
Fruit fly: Monitoring and bait spraying programs need to be implemented in Sunraysia and the Riverina. Fruit are at highest risk from colour break. A quick guide and I.D. chart is available from NSW DPI, NSW LLS and Citrus Australia.
Mealybug: The hot weather would have suppressed numbers and numbers are generally low.
Other: Some spined citrus bug sprays occurred for lemons during January and February and can still be a problem in March.
This Seasonal Update for Queensland has been prepared by Steven Falivene, NSW DPI.