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

Growing chestnuts are best suited to flat or gently rolling whenua. We recommend slopes that are less than 7 degrees to reduce erosion. This is to help with access and the operation of machinery.

Chestnuts need a soil depth of at least 100cm to grow well. Their shallow root system absorbs nutrients and water in the upper soil layers.

Specific soil fertility requirements for chestnut are not well known. Generally, for good chestnut growth and yields, various nutrients are required. These will include:

• Phosphorus - to stimulate root growth
• Potassium and sulphur - to contribute to the nut yield and quality
• Nitrogen - carefully managed to achieve high yields and limit vegetative growth
• Boron, iron, magnesium, and zinc - in smaller quantities to produce premium fruit.

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. A soil pH of 5.5-6.5 is optimal.

Soil safe Aotearoa

In Aotearoa, chestnuts are not highly vulnerable to temperature extremes. Because they flower late in spring, frost is not normally a problem for fruit set. Early autumn frost can harm the foliage and fruit so care should be taken at that time of the year. Temperatures above 31°C is helpful for nut ripening in mid-late summer. No days frost less than -4°C between 15-Sep to 31-Jan. Temperatures greater than 40°C may damage fruit. Annual rainfall that is greater than 800mm is suited.

Chestnuts need regular rainfall over the summer-autumn months as they are filling out the nut crop. Too much rain at any time can lead to root rot, and too little rain will affect the production of the nuts. Annual rainfall greater than 800mm is suited.

At harvesting, chestnuts have no specific rainfall requirements as the nuts will be washed after they have been picked up.

If you're thinking about growing chestnuts on your whenua, check the rainfall and rain intensity in your region. This is important while your chestnuts are forming and filling out nuts before harvesting.

See NIWA for more information.

Chestnuts are a perennial tree crop, meaning you will get one crop every year over the productive lifetime of the tree.

When planning to plant chestnuts, you will need to consider your geographic location and the best varieties of chestnuts to plant together. The most common varieties of chestnuts planted commercially in Aotearoa are the Euro/Japanese hybrids known as 1002, 1005, and 1015.

For advice on what varieties of chestnuts suit your whenua, talk to NZ Chestnut Council.

NZ Chestnut Council

Chestnuts are relatively versatile and will grow well in most areas of Aotearoa, New Zealand.

At least two varieties of chestnut must be planted together to enable cross-pollination and successful nut production. The orchard must be set out with thought to the placement of pollinator varieties, and this may require some experimentation in the location.

Suitable planting density is 100-300 trees/ha and they will start producing nuts after 3 or 4 years.

You should not need any special machinery to prepare your whenua for planting chestnuts. Not much is required in terms of maintenance except to mow or spray the grass under the trees to allow for harvest.

Chestnuts will grow for 3-4 years before they start to produce nuts with production increasing each year until they are at maturity (10+years).

Chestnuts are ready to harvest between February and April in the North Island, and between March and May in the South Island.

Harvesting chestnuts can be done by hand or using machinery and must be done daily as chestnuts start to deteriorate once they have fallen to the ground.

After harvesting the chestnuts from the ground, the nut is removed from the prickly burrs and stored immediately in a cool store.

After harvesting your chestnuts, the storage of your crop is very important. This ensures your crop can get to international and domestic markets in the best possible quality.

The chestnuts will be washed to remove any debris before being put immediately into a cool store and stored at 0-2°C.

Chestnuts can be affected by Phytophthora root rot, particularly in wetter and/or water-logged soils. Fungal diseases can also infect the nuts while they are still on the tree which can cause significant loss even under cool-store conditions. Pests like possums, rabbits and grass-grub are the major factors causing damage, especially to young trees.

You will need to consider using pest management methods, such as:

• fencing and tree protection
• monitoring crops to assess plant health
• making the environment attractive to insects that can eat pests
• targeted use of fungicides, pesticides and bait.

New Zealand Chestnut Council Inc

The NZCC aims to encourage, promote, and advance New Zealand's Chestnut Industry including the promotion of the sale and consumption, of fresh and processed New Zealand-grown Chestnuts, both in New Zealand and overseas, for the benefit of New Zealand Chestnut Growers. Members pay an annual NZCC fee of $130.00.

NZ Chestnut Council

Export market

Large tonnages are traded internationally, especially in Asia and Europe. Most of the NZ crop has been exported, although the industry now places greater emphasis on processing. Several companies exist to export and/or process NZ chestnuts. Many growers are shareholders in these companies.

Scale

The industry is small and is predominantly based around hobby growers. Currently, there are around 140 hectares of chestnuts produced per year in New Zealand. Most chestnut orchards are part-time operations of 2-3 ha. Some large orchards may be 10 ha or more. Turning a profit from producing chestnuts depends on several factors, like:

• your location - access to the market, or infrastructure, or to a packhouse
• 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 chestnuts. These include:

• basic garden equipment, for example, mowers, weed sprayers
• implement shed
• irrigation
• chainsaws
• shelter belts, and
• fencing.

It's estimated that you'll need to grow at least 3 hectares of chestnuts to offset the costs of investing in machinery and equipment.

Operating as part of a co-operative would be a practical way to reduce capital investment if you are producing on a smaller scale.

After harvesting your crop, you'll need a packing house and cool store to maintain the quality of your chestnuts. You'll need to sort, grade, clean, and pack your chestnuts into bags or crates, ready for the market. If you're located near a packhouse and can partner with them, they'll help you with this.

Jobs and people

Your people and labour requirements are seasonal, based on key milestones, like planting. You'll need a mixture of unskilled labour, as well as specialists. It is estimated that 1 person could harvest the nuts from a 3-hectare orchard and the low labour input required could work around other land use activities. The specialists will help you with:

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

The peak demand for labour and specialists by chestnut farmers is during planting and harvesting times.

Case study - Waikato chestnut orchard

Here is an example of an orchard in Waikato, let's imagine it had 10 hectares of chestnuts grown last year.

It yielded 75 tonnes of chestnuts, bringing in a revenue of $187,500.

It had $107,000 in expenses, and the farm made a profit of $80,500.

It took 10 years for the trees to reach full production.

Operational costs

The estimated operational costs to grow chestnuts are around $8,050 per hectare per year. This depends on factors, like:

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

Labour costs can be significant, especially when you're first setting up your orchard. Some other examples of costs that you'll need to consider are:

• rootstock
• fertilisers
• pesticides and herbicides
• skilled and unskilled labour
• permits, licenses, or certifications
• compliance with regulations and food safety standards.

Development costs are estimated to be around $$25,000-$40,000/ha.

Costs

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.

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

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

Revenue

Returns from chestnut farming are influenced by a variety of factors, including:

• market conditions
• yield
• quality
• production costs
• pricing strategies
• events beyond your control, for example weather conditions or market fluctuations.

Things that 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.

Operating profit

To estimate your operating profit, you'll need to look at the amount of money generated from selling your chestnuts, 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 chestnut crop area
• yield - the quantity of chestnuts 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
• root stock 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.

Most New Zealand chestnuts are sold domestically, with limited volumes exported (fresh or frozen) or processed. No known market access issues exist for processed chestnuts. In 2007, the export of fresh New Zealand chestnuts to the USA and Australia declined due to the USA and Australia’s requirement to devitalise nuts with methyl bromide. Continuing fresh exports now go to countries that do not require methyl bromide fumigation, and markets are dominated by Europe, Asia and the Pacific. The authorities can provide information on what's needed to export chestnuts, including:

• procedures
• documentation
• fees or licences
• packaging standards
• biosecurity requirements.

To export chestnuts you need to follow legislative requirements, including:

• Chestnuts are a prescribed product under the Horticulture Export Authority Act
• meeting export requirements, like documentation and packaging standards
• ensuring food is grown so it can be sold under the Food Act 2014
• meeting regulations around risks to freshwater.

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.