Orchard Setup
[Abstracted from New Growers' Intro]
What is involved in setting up a new orchard?
Purchase land - if you don't already own a property, then an important factor to consider when
selecting a site is the soil's drainage profile and nutrient levels. Also consider the climate (particularly
wind and extreme heat) and the availability of water for irrigation.
Soil tests - you should have a soil nutrient test done to confirm its suitability for any intended crop.
This will also help you plan any fertiliser. The results should be analysed by a specialist with experience
in hazelnut nutrient requirements.
Plan irrigation - your trees will need enough water to replace the moisture they lose through evapotranspiration.
If you will be taking groundwater, you will first need to apply for a resource consent for
the bore, then drill the bore and install the pump and finally apply for a resource consent for water
extraction. This may take several months.
Install irrigation - talk to an irrigation specialist about irrigation options. Most hazel orchards use
drippers or micro-sprayers to deliver water to each tree. You need to know how much water is
available before you can plan the irrigation system.
Rip, cultivate and level - ripping is required if you need to break up a clay pan in order to improve
drainage and root penetration. Cultivation and levelling may not be required if the property already has
a healthy green cover and is level.
Plant shelter - shelter trees are commonly planted 1 m apart, so a 4 hectare (10 acre) property with
66 m x 66 m blocks (nine blocks in a grid pattern) requires around 1600 shelter trees. Contractors may
be able to mechanically plant the shelter for you. Depending on the wind at your location, you should
consider letting the shelter grow for two or three years before planting crop trees.
Plant crop trees - hazels are usually planted in rows about 5 m apart and with the trees about 3 m
apart within each row (depending on the growth habit of the cultivar and local conditions- for more
vigorous trees, it may be necessary to reduce planting density later). This translates to around 600
trees per hectare, so the same 10 acre property would require around 2000 trees (if one block was left
unplanted for a house block).
Weed control - weeds compete for moisture and nutrients so control is important while the crop and
shelter trees are becoming established. Glyphosate (such as RoundUp?) is commonly used for weed
control, although a variety of non-chemical alternatives are also available (such as mulch).
Climate
Hazels are generally frost-hardy to around -14¢XC (and may require some winter chilling), although the
flowers and catkins are vulnerable to frosts of -8¢XC or lower for a short period in early winter. The trees
can suffer from overheating and sunburn in hot summer weather. Dry autumn weather makes
harvesting easier.
Different cultivars flower at different times in different locations, so your choice of crop trees and
particularly pollinisers will depend on your location.
Soil
Hazels tolerate a wide range of soils, but for optimal production you need a relatively fertile soil which
holds moisture but does not become waterlogged. You should have at least 30 cm of topsoil (and
ideally 60 cm) which is rich in organic matter. Hazels are more tolerant of too much water than too little,
so stony or sandy soils present a real challenge in maintaining an adequate soil moisture level.
Extremely heavy clay soils also present a challenge, and if there is a clay pan (or a ploughing pan from
previous use) you should rip to allow moisture to drain properly. You should consider the nature of the
soil in relation to the local climate and rainfall levels - hazels can thrive on both clay soils and light soils,
provided their water needs are met (via rainfall and/or irrigation).
You should have a soil nutrient test done for any property you are considering. An excess or deficiency
of particular elements can harm the trees, and although you can use fertiliser it is difficult to fight the
underlying nature of the soil. Soil should be neutral to slightly acid (pH 6).
Shelter
Hazels are easily damaged by strong winds, so good shelter is essential (especially in windy areas
such as Canterbury or the Wairarapa).
If you purchase land with shelterbelts already established, you need to consider whether they are
appropriate to your requirements. Shelterbelts for stock protection are often dense and evergreen, and
this may not be suitable for an orchard. However, the shelterbelt could provide initial protection as your
orchard becomes established (including your new shelter) and could be removed at a later stage.
If you are starting with bare land, it is a good idea to plant the shelter first and allow it to become well
established - in most cases, the hazels can be planted two or three years later. If you choose not to
wait, your trees may suffer - regular strong winds may slow their growth; because they are struggling to
survive in the elements, they may be weaker overall and more vulnerable to pests and diseases;
branches may break, which may make pruning more difficult later. However, planting the hazels at the
same time as the shelter may allow cropping one or two years earlier than waiting.
Shelterbelt design is an important part of planning a new orchard - the maximum block size will depend
in a large part on what shelter species you choose. Most shelterbelts use fast-growing deciduous
species that will grow to 15~30 metres, such as poplars and alders. Be aware that some shelter
species (such as poplars and willows) have vigorous root systems and will compete with your crop
plants for water. Different varieties of each species have different growing habits and requirements,
and some varieties may be susceptible to diseases under certain conditions. Talk to a local tree
nursery that has experience in shelter design - they should be able to recommend appropriate shelter
species for your conditions and help you determine the appropriate block size.
Orchard layout
Block sizes may vary from 50 m to 90 m and blocks do not need to be rectangular. You should
consider the prevailing wind direction when designing your orchard as this will affect block size and
polliniser layout.
You will need to allow enough space for maintenance equipment (such as mowers, sprayers,
harvesters or fertiliser spreaders) to access and work in your blocks.
More information on orchard design, such as tree spacing and cultivar selection, will be included in the
Hazelnut Growers' Manual (scheduled for release in June 2009).
Orchard floor management
There are several different options for orchard floor management. The most common approach is to
use grass (often a slow growing variety such as fescue, which reduces the amount of time required for
mowing, or else regular pasture grass), but you could also use a herbal ley to bring nutrients up from
deeper in the soil and to improve your soil structure, or potentially plant a cash crop (such as lucerne).
To a large extent this decision depends upon your philosophy and priorities.
For planning purposes, it costs around $1500 per hectare to spray out and cultivate land (whether to resow
grass or to establish some other crop). You should discuss your particular situation with a local
farm supplies expert.
Even if you do not cultivate and re-sow, it is important for harvesting that the orchard floor is level.
Detailed information about the pros and cons of the different orchard floor options is available in the
Hazelnut Growers' Manual.
Irrigation
Hazels prefer a relatively moist environment and may die if stressed by lack of water (particularly if
drying winds occur on warm, sunny days - a common occurrence in many locations in New Zealand).
Even if the trees do not die, if they are stressed they will not grow as well or produce as good a crop.
Your irrigation system design will depend on the water you have available and the profile of your soil.
You will need to be able to replace the moisture lost through evapotranspiration, which may be up to
5 mm per day in summer.
It can be expensive and time consuming to have a bore drilled and to gain the necessary resource
consents to use the water. Allow up to 3 months for a water use consent; you may also need to seek
advice from an environmental planning consultant. Consent to drill a bore does not guarantee you
consent to take and use groundwater, so check whether there are any restrictions in your area.
Sprinklers are the most commonly used system, although drippers may also be suitable in heavier soils
(bear in mind that the root zone will extend as the trees grow so you will need to broaden the dripper
zone in later years).
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