Hazelnuts are a relatively hardy tree and will withstand some degree of adversity and neglect, however, if you hope to get quality and quantity of nuts there are some important considerations to attend to in the planning and maintenance of your orchard, whether you are planting two or two thousand trees.
Site and Soil
Hazels prefer a reasonably fertile soil with good soil moisture but adequate drainage. They will tolerate frosts but established wind shelter is a must. Persistent harsh winds will slow the growth of your trees and hence also affect their productivity. If your shelter is not yet well developed you should consider the use of individual tree guards with ventilation.
When planning orchard layout you will need to allow for root competition from shelter trees if a variety such as pines or poplars have been used. Side pruning will be required as part of your ongoing maintenance programme if you use these types of trees. We would recommend the use of a tap rooting tree such as Italian Alder as the preferred orchard shelter.back to top
Depending on the variety, allow 2.5-3m between trees for whiteheart variety which are smaller in size at maturity and 4-5m for the more vigorous types. Allowing at least 4m between rows with a consideration for the type of equipment you will be using as your orchard is established.back to top
The area for planting should be marked and cleared or sprayed with herbicide. Ripping may be required depending on your soil type. The bag should be removed from the base and roots gently loosened without major disturbance during planting out.
If your trees are bare rooted keep them moist and the roots wrapped or heel into your vege garden until ready for planting. No further trimming will be required. Water well after planting.back to top
Varieties & Pollination
Hazelnuts come in many different shapes and sizes, however Whiteheart is the variety currently favoured by most orchardists in the South Island. This tree grows to about the size of a vigorous apple tree producing quality and flavoursome nuts of a smaller size excellent for the cooking and processing market.
The trees are wind pollinated from catkins of another variety. At least 10% of your planting needs to be in pollinator varieties planted with consideration to your prevailing winds. We recommend 2-3 types of pollination for best results. These trees will produce their own nuts of differing sizes, shapes and quality.
Common varieties available in New Zealand
Known as a ‘universal’ pollinator this variety produces midseason catkins, but for a relatively short pollen shed time and has larger round nuts.
Has a reputation as a prolific producer of pollen shed over a longer period well suited to catch whiteheart flowering times in Canterbury.
Another prolific pollen producer and useful for early pollination. Produces larger nuts and a vigorous tree.
Bred for Whiteheart pollintation to be planted in combination to provide a long pollen shed period and maximum pollen coverage.
There are a many other varieties available but these are the types most commonly planted in the South Island at present. Pollination and flowering times may vary a little between locations and seasons.back to top
Either with herbicide or mowing or a combination of both to keep a clean orchard floor, essential to prevent competition for water and to enable collection of nuts either manually or by vacuum machinery in February/March.
Other management options to consider are planting grassy strips in one of the new generation slower growing grass seed varieties or sheep grazing for the first few years that your orchard is getting established (heavy duty stakes and secure tree guards will be essential for this option).
Left to their own devices hazels will grow vigorous suckers from the base and form a dense bush which makes management difficult. For best results we suggest controlling suckers by manual removal or contact herbicide and pruning the tree to a single stem vase shape.
In most areas of the South Island irrigation during the summer months will be necessary. The best way to be sure of the moisture levels in your soil is to dig a hole alongside the trees.
In an orchard fertiliser requirements can be established by a bi-annual leaf and soil analysis.back to top
Young hazels can develop disease problems especially during spring when foliage is soft.
Weather patterns resulting in increased humidity, long wet periods followed by hot days and high diurnal temperature fluctuation as well as the use of poorly ventilated tree guards, heavy mulching or overhead watering can all create a situation ideal for the development of fungal or bacterial diseases.
Of particular concern are bacterial and fungal blights. We suspect that there may be incidences of one or other of these diseases now occurring in hazel orchards in New Zealand.
Note that not all leaf damage is not necessarily caused by disease but physiological factors such as wind damage, drought stress, spray drift, hail damage, etc. Can also stress the plant.
Plants will be more disease resistant if they are healthy and grown in good conditions.
The best advice we have at this time for the control of these diseases is to spray as follows:
- Spray with Kocide or Mancocide in the autumn prior to leaf fall, again after leaf fall and a third time in early spring before bud burst.
- If disease becomes apparent or is suspected, prune out infected material and dispose of by burning, follow with further Kocide or Mancocide spray.
- In situations where soils are heavy and wet root rots may be a problem, Agriphos 600 has been used with good results.
- If unsure seek professional advice.
Once trees are established they tend to tolerate adverse conditions well and are more resistant to disease threat. These recommendations are particularly for young and newly planted trees. Good orchard management and plant health are your first defense against plant disease.
Big bud mite is the only pest at present that is a significant problem in New Zealand, this infests the buds at development stage effectively killing it and slowing the growth of young trees. It can be effectively controlled by manual removal of affected buds in winter.
There have also been reported instances of leaf roller and scale insect reported from orchards in the South Island.back to top
Hares and Rabbits
May also be an initial problem if you are planting smaller trees, tree guards or repellent may be required in areas with a large population until the trees are well established.back to top
Each property and orchard will have its own characteristics and careful planning in the early stages of development is vital. We are happy to assist with any queries you may have.
We may also be able to assist with your orchard maintenance programme if required.
New Zealand's Hazelnut industry is still in its infancy with the oldest commercial orchards at 12-14 years. So much of the local knowledge gained is through overseas literature, Lincoln University Research and grower experience. Markets are still being established as the quantity of product gradually increases but there is increasing interest in the high quality nuts we can produce.back to top