“A job worth doing is worth doing well.”
Our 5 Tips for Better Summer Spraying Results.
The last few summers have been strong reminders of the importance of retaining subsoil moisture through an effective summer spraying program. The lack of summer rainfall and very late breaks has meant going into sowing with little to no stored moisture and relying on in-season rain. It should be a priority for growers to get summer spraying right.
- Summer spraying is not a luxury item. It should be considered an essential expense.
- The financial rewards of timely summer weed control far outweigh the costs.
- Expenditure on summer weed control can be minimised by spraying early.
- Control can be maximised by spraying under the right conditions, ensuring droplet survival and penetration into the target.
Given that one application of herbicide over summer can cost $15-$25/ha, it pays to ensure maximum return on every dollar spent.
So, here are our 5 Tips for better summer spraying results:
1. Select the right product, the right rate and the right time (and save time and money).
Product selection will be influenced by weed spectrum, weed size and the degree of stress that the plants are under. Make sure what you’re using is designed for the weeds you are targeting.
Timing: Spraying within 2 to 4 weeks after germination is the key to achieving good results. The benefits of early and on-time spraying include minimising soil moisture and nutrient loss. Spraying early also appears to reduce wheel-tracking problems. Also, late spraying on more established weeds will require higher herbicide rates. This increases the cost of the operation, plus results are often variable. Not to mention, the damage has already been done in terms of seed set, soil water and nutrient loss.
2. Keep the rates up.
Keeping glyphosate rates robust will help counteract less-than-ideal conditions. Skimping on summer weed-spraying rates can be counterproductive. You may need to apply a second spray. Do it once, do it properly.
3. Keep the water rates up.
Keep your water rates up. We recommend 80 to 100 litres. Higher water rates improve efficacy by ensuring better coverage, particularly when using coarser nozzles (as required when now using 2,4-D products).
4. Include SOA and LI700 (or save time and use Outright 770)
Always add ammonium sulphate (SOA) and a penetrant regardless of water quality. Research has found 0.25% LI700 to be equally effective as 1% Hasten on heliotrope. Oil-based adjuvants may be required to maintain droplet size and on particularly woody weeds.
Or, why not give Outright 770 a try? It’s a 3-in-1 drum-based formulation to save you time (Hasten, Non-Ionic Surfactant, and SOA).
5. Be vigilant when using 2,4-D.
Always take care when using volatile 2,4D products (Ester 680/Amicide) and comply with APVMA regulations. Our top 5 requirements for spraying 2,4-D products include:
– Don’t spray during conditions where there will be an inversion layer
– Spray only during wind speeds between 3-15km/h
– Boom height must be at a maximum height of 50cm above the crop canopy
– Spray nozzles have to be a minimum of Very Coarse droplet size and no smaller. But in summer, the APVMA advises using Extremely Coarse to Ultra Coarse nozzles. We recommend just going straight to Ultra Coarse and using these as your summer spraying nozzles, but ensure correct water rates are used to ensure efficacy.
– Keep spray records of everything. Make sure you’ve got yourself covered.
Contact our agronomists if you have any questions.
