Maize grows best in deep, well-drained, fertile soils. The soil should not be prone to waterlogging and have good nutrient retention.

Growing maize requires a range of farm operations that most farmers don't have the specialised machinery to carry out. Therefore, much of the work is contracted out to agricultural contractors with very large and heavy machinery.

Slope is very important when considering growing maize (grain). The most suitable whenua will be easily accessible and flat - less than 3 degrees. With a slope of 3-7 degrees erosion risk increases and should be mitigated. This is to help with the access and operation of this heavy and wide machinery.

Maize needs a soil depth of between 100 - 150cm to grow well. Their fibrous root system absorbs nutrients and water from the deeper soil layers when necessary.

For good maize growth and yields, various nutrients might be required. This includes:

• Phosphorus - to stimulate root growth
• Potassium - to regulate water content in the plant and contribute to plant health
• Nitrogen - carefully managed to achieve high yields
• Manganese, magnesium, and zinc - in smaller quantities to produce premium cobs.

It's important to test your soils before planting your crop. Many companies offer this service. This will help you understand the current fertility of your block and nutrient requirements.

Soil safe Aotearoa

In Aotearoa, maize is planted in spring between October and December. It needs soil temperatures above 10°C for seed germination, and temperatures within 21 - 27°C for ideal growing conditions. Frost during flowering needs to be less than -1°C from 15-Sep to 15-Oct. Frost during harvest needs to be less than -1°C from 15-Mar to 15-April.

Maize is a deep-rooted crop so is often grown without irrigation. Too much rain or ponding of water can lead to rot and too little rain can affect the growth of plant shoots and grain.

If you're thinking about growing maize on your whenua, check the rainfall and rain intensity in your region. This is important while your maize is growing and at harvesting.

See NIWA for more information.

Maize is an annual crop, meaning you will get one crop over 12 months.

When planning to plant maize, you will need to consider your geographic location, the types of maize suited to this location, and your intended output. Different varieties of maize will grow better, or at different times on the North Island than on the South Island. For advice on what type of maize best suits your whenua, talk to your local seed company representative. For example, Corson Maize.

Corson Maize

There are four main phases of maize growth:

1. emergent phase, when the seed is germinating,
2. vegetative,
3. tassel phase, and
4. reproductive growth phase.

You may need machinery to prepare your whenua for planting maize. Usually, the planting is contracted out to an agricultural contractor with the appropriate machinery.

Maize germinates when the temperature and moisture conditions on your whenua are favourable. In Aotearoa, this is usually during October - December.

Maize will grow for 4 - 6 months before it is ready to be harvested. When the moisture content of the grain is between 20 - 24% harvesting can begin.

Harvesting maize is done using specialised machinery and is usually contracted out to agricultural contractors. The timing will be dependent on the moisture content of the grain.

After harvesting, the maize is transported to a processor and stored in a silo to await processing.

Harvesting maize is done using specialised machinery and is usually contracted out to agricultural contractors. The timing will be dependent on the moisture content of the grain.

After harvesting, the maize is transported to a processor and stored in a silo to await processing.

Maize can be affected by viral and fungal diseases and pests like Argentine Stem Weevil and Black Beetles. Animals like Pūkeko, ducks, and pheasants will also be a problem. You will need to consider using pest management methods, such as:

• counting the number and species of pests weekly
• monitoring crops to assess plant health
• making the environment attractive to insects that can eat pests
• targeted use of fungicides and pesticides
• other pest control methods.

The Foundation for Arable Research Incorporated (FAR)

The Foundation for Arable Research Incorporated (FAR) creates new tools, knowledge, and technologies to support arable farmers. FAR's activity is funded by a compulsory levy.

Most local maize grain is sold for poultry and pig feed, with silage maize grown to feed dairy cows. The majority of maize grain is produced in the Waikato/Northland regions. Maize is relatively easy to grow and is often produced through lease agreements between landowners and contract growers.

Approximately 150,000 tonnes of maize grain are imported into New Zealand each year. This is more than New Zealand exports.

Export market

Most maize produced in New Zealand is used domestically as stock feed (for poultry, calf and dairy cows). A smaller amount is used to produce starch and in human food products like corn chips. The export market is very small, with some maize grain exported to the Pacific Islands and Australia.

Read more about New Zealand Grain and Feed Market Situation.

Scale

Maize can return a profit from a small (5-hectare) or large-scale enterprise. Turning a profit from growing maize depends on several factors, like:

• your location - access to the market, or infrastructure, or to a silo
• your production practices - modern machinery and equipment or smaller scale efficiencies
• the market demand and access to the market
• your operational efficiencies - larger farms may benefit from economies of scale.

Equipment and infrastructure

There are various tools and equipment needed for growing and harvesting maize. These include:

• tractors and other field machinery, for example, combine harvesters
• ploughs
• harrows
• truck and trailers
• seeders
• silos
• cultivators, and
• irrigation systems.

It's estimated that you'll need to grow at least 5 hectares of maize to offset the costs of investing in production. Contractors would need to be used if you are producing maize on a smaller scale and it is uneconomic to invest in equipment and infrastructure.

After harvesting your maize, it needs to be dried and stored in silos.

Jobs and people

The labour inputs required are low because the crop is machine planted and harvested. Most maize growers utilise contractors. If you are managing the crop yourself you will need expertise in cropping.

You can contract expert advice to help you with:

• managing the crop cycle,
• pest management techniques,
• harvesting and,
• post-harvest management.

The peak demand for labour and specialists by maize farmers is during planting (October-November) and harvesting times (March).

Case study - Gisborne maize enterprise

Here is an example of a maize enterprise in Gisborne, let's imagine it had 25 hectares of maize grown last year.

It yielded 290 tonnes of maize, bringing in a revenue of $125,000.

It had $50,000 in expenses, and the farm made a profit of $75,000.

It took 5 months for the maize to be ready for harvest and then sold (time to commercial yield).

Operational costs

The estimated operational costs to grow maize from spray out to covering the stack is $2000/hectare. This depends on factors, like:

• scale of the operation
• level of mechanisation
• specific farming practices
• regional and locational factors
• market conditions.

While the labour costs are low because machinery is used for planting and harvesting, there are many other production costs. Some other examples of costs that you'll need to consider are:

• seeds or sets
• fertilisers
• pesticides and herbicides
• agrochemicals for onion cultivation
• cropping expertise
• permits, licenses, or certifications
• compliance with regulations and food safety standards.

Read more about how contractors navigate maize costs.

Costs to consider

There are some costs you will need to consider, and these will change with the amount produced. Here are some examples:

Yield (and time to profit)

It typically takes several years to establish a sustainable and profitable operation. n New Zealand maize crops produce around 11.5 tonnes per hectare.

Maximising the amount of good quality maize grown will increase the profits you earn. Factors that can contribute to higher maize yields include:

• crop management
• variety selection
• planting density
• nutrient management
• weed control
• harvesting at the right time.

Revenue

Returns from maize production are influenced by a variety of factors, including:

• market conditions
• yield
• quality
• production costs (because growing contracts are always signed at the start of the season, input costs may vary between sowing and harvest times).
• pricing strategies
• events beyond your control, for example, weather conditions or market fluctuations.

Read about crop losses due to weather events.

Things we can do to create better returns include:

• efficient practices to maximise yield and production.
• market demand and pricing
• quality and grading
• Cost management
• Storage and post-harvest handling
• Value-added opportunities

To help you make informed decisions and maximise returns, it's important for you to:

• stay informed about market trends through research.
• maintain good relationships with buyers.
• regularly assess your farm's production and financial performance through tracking costs.

The Foundation for Arable Research (FAR) has developed an excel template that growers can use to help them predict crop production costs and gross margins.

Arable costs of production template

Operating profit

To estimate your operating profit, you'll need to look at the amount of money generated from selling your maize, minus your production costs. Some factors may affect your revenue and influence your farm's operating profit. These include:

• farm size or the size of your maize crop area
• yield - the quantity of maize sold
• market conditions and fluctuations
• production costs and efficient farming practices
• pricing strategies
• weather conditions.

You will need to consider your production costs, which can include:

• labour
• seed costs
• fertilisers
• irrigation
• pest and disease management
• machinery maintenance
• storage
• packaging
• marketing costs.

These costs can be affected by having efficient farming practices and effective cost management.

Each farm will have factors specific to them and different market dynamics. Keeping accurate records of your production and financial records can help you see where improvements could be made and increase your operating profit.

The Foundation for Arable Research Incorporated (FAR) collects an Arable Commodity Levy of $1 for every 10,000 seeds purchased. The levy is added to the price when you buy seed.

Learn more about levies.

You must comply with National Programme 1 requirements under the Food Act 2014. This includes:

• following safe food practices, like checking for pests and using clean water
• registering your business with either your local council or MPI
• getting your business verified.

Learn more about National Programme 1.

You will need a freshwater farm plan, either now or by 2025 if your whenua will have:

• 20 hectares or more of arable and/or pastoral use, or
• 5 hectares or more of horticultural use, or
• 20 hectares or more of combined uses.

These plans identify actions to manage and mitigate risks of on-farm activity to freshwater. They must be certified and audited, then recertified every 5 years.

Learn more about freshwater farm plans.

Some additional certifications and registrations may make your maize more appealing to buyers.

You can choose to get certified with NZGAP for a yearly fee. Some retailers and wholesalers only take crops from an NZGAP-certified supply channel.

Learn more about NZGAP.

For example, organic certification of maize grain used as stock food commands higher prices (20 kg conventional maize $27.50 compared with organic maize $61.43).

MealTime Maize Chook food 20kg