Maize for Grain
Insight 338


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The economics of contract growing maize grain are largely dependent on crop yield and the price received per tonne of maize grain ($/tonne).

As a guide the approximate fixed and variable costs to grow maize grain in New Zealand during the 2017/2018 season are shown below.  Please contact your local farm supply store, grain merchant or contractor to establish current costs in your region.

 Table 1: Estimated gross margin analysis for growing maize for grain

Maize returns are driven by crop yield and the maize grain price. Contact your local grain merchant for up to date maize grain pricing.



Approach a grain merchant to establish your grain marketing plan. This contact will enable you to choose which market you wish to produce grain for. With the assistance of the merchant and your Pioneer Representative, a suitable Pioneer® brand hybrid (or hybrids) can be selected to fill that market requirement. Stock Feed – Wet Starch – Human consumption (Grit)

Sale of grain

Grain is normally traded per tonne at 14% moisture.


PADDOCK Selection

Ideally the paddock selected to grow the crop will have the following characteristics:

Contour and accessibility

Relatively flat to easily rolling contour is recommended to enable the passage of large machinery with safety. Check gateway widths, loading capacity of culverts or bridges and ensure the access route to the paddock is clear of overhanging branches and power lines for ease of access by large machinery and trucks.

Crop security

It is important to ensure the area is securely fenced so as to avoid stock damage.


Maize plants do not perform well in water logged soils. Wet areas can encourage weeds to dominate the crop. It is important to ensure surface ponding does not occur. Desirably the area would have soils with good moisture retention characteristics and nutrient holding capacity.

 Soil testing

Areas planted in maize grain should be soil tested on an annual basis.  Take soil samples to determine lime and fertiliser inputs required to bring the soil nutrient status to the desired level.


Refer: Pioneer Technical Insight 332: Fertiliser Application for Maize Crops for further details.



Spray out of pasture

If the area to be planted in maize is currently in pasture it is desirable to spray the area with a glyphosate based herbicide.  The area requires to be checked thoroughly for perennial weeds prior to this occurring.  If any problem weeds (e.g. Mercer grass, couch or yarrow) are identified, contact your local herbicide company representative to determine the appropriate rate and /or mixture of herbicides.


It is important that cultivation depth be kept to a minimum (preferably no greater than 150 mm). Generally the greatest nutrient levels are found in the top 150 mm of the soil. Cultivation to greater depths can lead to a dilution of soil fertility and moisture holding capacity. Increasingly reduced tillage management methods are being implemented. These operations leave more stubble on the surface which helps to reduce soil erosion and nutrient losses.

 Fertiliser and lime application

Soil test to determine soil nutrient levels and obtain professional advice as to rates and timing of fertiliser applications. While it is important to ensure crop requirements are met, don’t apply more nutrients than you need. If a significant amount of potassium is required in the base dressing an interval of 7–10 days between fertiliser application and planting is desirable on light soils or dry peat soils. This interval will reduce the likelihood of “fertiliser burn” to the seed or seedling.

 Seedbed preparation

Cultivate to achieve a fine, even seedbed. This facilitates good seed to soil contact for good germination and also allows soil chemicals and insecticides to perform at their optimum. An even, clod free seedbed allows planting machinery to function accurately giving uniform seed placement.


Maize is planted with precision planting machinery which may also band the starter fertiliser to one side and slightly below each row of seeds. Uniform placement of seed within a row is essential to gain optimum performance from your Pioneer® brand maize hybrids. Pioneer provides a free Seed planter check service to maize contractors to ensure their planters are calibrated accurately.


Seedling maize plants are vulnerable to several insects, namely, Argentine stem weevil, wireworm, greasy cutworm and black beetle. Planting insecticide treated seed is the best option and Poncho® is the preferred choice because it controls Argentine stem weevil, greasy cutworm and black beetle. Always ask for Pioneer® Premium Seed Treatment to ensure accurate and precise chemical application. Every bag of Pioneer brand seed is mechanically stitched closed with a green and white bi-colour tamper proof string. This ‘locks in’ the Pioneer warranty and seed replant risk cover.

 Starter fertiliser

Starter fertiliser may be recommended and is a specially formulated mixture of either, nitrogen and phosphate, or nitrogen, phosphate and potassium. Some mixtures are formulated “blends” where the individual components are mixed to a known ratio. Specialist product known as compound starters are granulated products where each granule is formulated to the specific nitrogen, phosphate and/or potassium status desired. Correct positioning and placement of the starter fertiliser in relation to the maize seed row is important to avoid seed and seedling crop damage, especially in light free draining soils. Refer to your soil test results and your fertiliser representative or farm merchant for advice on the correct product for your crop.

 Herbicide use

Good weed control is essential for a high yielding crop. Choice of correct herbicides, timing of application and the monitoring of the crop throughout the growing stage of the crop are all pre-requisites of a successful outcome. Weed control falls into two categories - grass weed, and broadleaf weeds. Both are equally important. Contact your merchant, contractor or herbicide company representative for weed control advice.

 Crop monitoring

During the establishment stage of the crop it is important to check the crop at frequent intervals for indications of weed infestation and insect or bird damage. Once the crop has tasselled, continue to check it looking for signs of insect damage.

Throughout the life of the crop regular checks are required right up to harvest to ensure the crop is free of leaf, stalk or grain infections.  Your farm merchant or local Pioneer Representative will be able to offer support if you have any concerns.

 Nitrogen sidedress application

Since the maize crops demand for nitrogen is high, it is important to ensure that crop requirements are met. Additional nitrogen may be required approximately 5 - 6 weeks post planting. To determine if your crop requires additional N take a deep N sample (60 cm) 2- 4 weeks post-planting. Deep N results can be run through AmaizeN, a fertiliser forecasting tool developed for maize, to determine nitrogen fertiliser requirements.

 Tasselling and pollination

This normally occurs in New Zealand maize crops between 75 - 85 days post planting depending on weather conditions and temperatures experienced during the early (vegetative) growth stage of the crop.


Monitoring of the grain moisture content during the “dry-down” phase will enable timely harvest to be undertaken. “Ideal” grain moisture content at harvest is generally considered to be between 22 - 24%. Usually your merchant representative can help with crop moisture monitoring.

 Harvest practices should attempt to minimise the amount of soil compaction in the cropping area. Selecting laneways throughout the paddock will limit compaction damage. The laneways can then receive special cultivation treatment to overcome any compaction if considered necessary.

 Care in handling of grain is important. The aim is to maintain the integrity of each grain. Excessive chipped and cracked grain may carry payment penalties. Ensure all augers are well maintained and unload grain onto grain when filling bulk bins. Grain stored in bulk bins awaiting transport should be protected from rain.

 Stubble management and post-harvest land use

Several land use options are available in the period between maize crops. Some growers choose to leave the area “fallow” over the winter period. Ideally the stubble should be shredded and the area shallow cultivated (normally using discs or power-harrow) to incorporate the stubble to the extent of approximately 50% into the soil. This practice promotes the rapid break-down of the stubble which in turn reduces the likelihood of fungal disease carry over to the next crop.

 The root system of annual ryegrass plants offer an excellent source of carbon material which will assist in maintaining the organic matter content of the soil.

 In warmer areas, Italian ryegrass and/or oats can be planted into the cultivated stubble mix. This winter crop can be harvested as silage prior to cultivation being undertaken for the next spring’s maize crop. Many growers spray the Italian ryegrass and/or oats with glyphosate prior to harvesting the silage to save time.

 A third option is to direct drill an Italian type ryegrass into the soil over the stubble. The ryegrass may then be lightly grazed at appropriate intervals by stock. It is desirable to remove stock from the paddocks when ground conditions are wet to avoid treading damage to the cropping soil. At all cost avoid using the maize cropping area as a “stand-off pad” for dairy herds.

 Increasingly reduced tillage management products are being implemented. These operations leave more stubble on the surface which will require careful management at planting. 

Pioneer® brand products are provided subject to the terms and conditions of purchasing, which are part of the labeling and purchase documents.

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The information in this publication is general in nature only. Although the information in this publication is believed to be accurate, no liability (whether as a result of negligence or otherwise) is accepted for any loss of any kind that may arise from actions based on the contents of this publication.

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Revised: August 2017
Expires: August 2018