Agronomy, events, Fertiliser, Nutrients, Projects, Research, Vegetables

Nitrogen Management Field Day – Levin 23 Jan

Many thanks to Woodhaven Gardens for hosting the Nitrogen Management Field Day we ran in Levin with VegetablesNZ. Thanks also to Antony for bringing hard copies of the new good practice guidelines, “Nutrient Management for Vegetable Crops in New Zealand“.  

We began the day with Luke discussing soil sampling strategies to make sure samples are representative. This involves taking at least ten samples, more from large areas, and ensuring samples taken fairly represent the variation across the vegetable bed and across the whole block or paddock.

Luke leads discussion about soil sampling methods to get good results

Georgia presented the Quick Nitrate Test method and the kit that is avaiable to growers. We use the test frequently in our trials and to guide nitrogen fertiliser use at the MicroFarm. We find the shaking of soil in the test-tube is important if reliable results are to be obtained. You must allow the extract solution to access all the soil to release the nitrate.

Georgia presents the Quick Nitrate Test

Woodhaven agronomist, Karen talked about their experiences using the Quick N-Test. They paired the quick test with standard lab testing while they learned how results are affected by soil variations and soil moisture levels. They don’t take the exact quick test result numbers, but use them to guide adjustments to their fertiliser application rates.

We demonstrated three alternative methods for applying liquid fertilisers; TeeJet, Stream Bar and home made Y-Drops. We think liquid fertiliser can offer significant benefits by enabling easier splitting and more accurate applications and reducing the risk of leaching while helping maintain excellent crop nutrition.

Droppers split near ground level and apply streams of liquid fertiliser to the soil beside row crop plants. This type of application is an alternative to banding dry fertilisers

The Y-Drop system is suited to row crops such as corn, broccoli or other brassicas. It drags soft hoses along the plant rows applying a stream to either one or both sides, close to the plant where uptake is most efficient. 

TeeJet nozzles (left) and Stream Bar (right) apply streams of coarse droplets that tend to run of plants and avoid risk of burning foliage. These are alternatives to broadcasting dry fertiliser

The TeeJet and Stream Bar systems replace standard spray nozzles, given a curtain of droplets along the boom. The TeeJet has diverging streams so application spacing can vary if the boom rises or falls. The Stream Bar tends to maintain a more uniform application. These systems are alternatives for crops such as baby leaf, baby beetroot and lettuces where dry fertilisers would be broadcast.

This field day was part of our Future Proofing Vegetable Production project and was held with support of Woodhaven Gardens, Pescini Bros and Vegetables New Zealand along with our major Project Sponsors.