Gisborne District Council's Tairawhiti Resource Management Plan (TRMP) includes rules for applying fertilisers. Incorrectly applied fertilisers can have negative effects on the quality of freshwater and habitats for fish life.
When aerial dressing, make sure fertiliser is at least 5m from all outstanding waterways.
Use good management practices when ground dressing fertiliser
Fertilisers can include
- Nutrients like nitrogen, phosphorus, potassium, sulphur, magnesium, iron, zinc like boron.
- Fertiliser additives to help plants absorb nutrients.
- Soil conditioners to alter the soil.
Applying fertiliser correctly
The Tairawhiti Resource Management Plan has rules for applying fertiliser correctly:
- When applying fertilisers you must follow the Code of Practice for Nutrient Management
- Fertiliser storage and loading sites need to be at least 50 metres away from streams, lakes and wetlands.
- Nitrogen fertiliser applications of more than 200kg N/ha/year need to be in split dressings of 50kg/N/ha.
- Soluble phosphate fertiliser applications of more than 100kg P/ha/year need to be in split dressings.
- You must apply fertilisers by hand if within 5 metres of a waterway listed in the TRMP Part G Schedule G7 and G18.
Good fertiliser management
- Make sure operators know what application rate you want.
- Create a map for operators so they can see the boundaries for application. Note the features to be avoided, such as streams, lakes, ponds, wetlands and riparian strips.
- Specify the accuracy and evenness of the spread required.
- Choose the right mix of fertilisers for safe, efficient spreading without clumping or separating.
- Rainwater can cause fertilisers to run-off instead of being absorbed into the soil.
- After a drought, avoid losing fertiliser in the first rainfall and wait to apply it after some rain.
- Avoid applying fertilisers when moisture in the soil is too high, at or near field capacity.
Consider planting riparian buffer strips around permanent streams.