Tree growth during establishment years is critically important to the success of an intensive orchard. Any factor that inhibits growth will wind up costing growers through tree replacement and often delayed bearing. 

Properly preparing the planting site for an intensive pear orchard is integral to achieving maximum growth and productivity in the first few years of establishment.

Planning Early

Evaluate the Site

Replanting Existing Sites

Site and Soil Preparation

Further information

Planning Early

Planning site development should be done well before replanting, particularly if the site is an old/existing orchard block. Growers should be planning developments at least 2-3 years in advance to allow for enought time to

• prepare an accurate budget 
• order trees
• order trellising and irrigation systems
• plan labour, cultural practices and equipment requirements
• identify and correct any drainage or nutrition problems and,
• determine if fumigation is required

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Evaluate the site

Before the final decision is made to develop a site, it should be thoroughly evaluated. An evaluation should take into account the site suitability for pears. It is particularly important to understand

• drainage
• soil type
• slope
• prevailling winds
• aspect
• frost susceptibility

This may require mapping of the area to identify issues and plan for corrective measures. If it is a replant site it is particularly important to analyse the past history of the orchard and identify potential problem areas.

Soil Test

It is imperative to obtain a soil test before preparing the site. This will identify whether you need to apply nutrients or improve soil.  

pH, nutrients, salinity and organic matter

Soils should be tested for pH, soil nutrients, salinity and organic matter so that any ammendments can be made before planting. If surface runoff during irrigation indicates slow soil infiltration rates a test for gypsum requirement may also be needed.

A subsoil sample to check pH and gypsum requirement is useful if the site has been replanted more than once.  

Risk of replant disease when replanting old blocks

Replant Disease is one such factor that can cause poor growth and sometimes death in newly planted orchards. Replant disease can be specific or non-specific. Specific replant diseases  such as Specific Apple Replant Disease (SARD) affects apples planted directly after apples. Non-Specific replant disease can affect apples planted after other fruit crop species (eg. stonefruit) or other fruit crop species planted after each other (eg. cherries after apples).  

The exact causes of replant disease are still yet to be identified but it is widely attributed to a combination of soil borne organisms such as parastic nematodes,  and soil borne fungi and bacteria.

Recognising replant disease is often not easy initially, a range of factors need to be considered. Above ground the main symptom is a general lack of tree vigour and a failure to thrive. Below ground the roots can be blackened, very few root hairs and a tendency for premature decay of the roots. Replant disease is generally non-lethal but tree deaths can occur in newly planted trees, often another pathogen is also associated with the tree death. Affected trees tend to recover and make normal growth after 2-3 years however the economic impact of the delayed production and low early year yields can be very serious. It can turn a potentially profitable orchard into a poor or negative investment.

Pears are generally regarded as being less susceptible to replant disease than species such as apples. However, precaution should still be taken when planting pears on more dwarfing rootstocks such as quince into existing fruit blocks - and particularly old pear blocks.

Bioassay tests of soils can give an indication of the affect the soil will influence the growth of young trees and whether or not soil fumigation or other ammendments are needed.

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Replanting existing sites

Trees should be removed immediately after harvest - if conditions enable easy removal of trees an roots. Timing and method of removal will depend on the site conditions, costs and availability of equipment.  

                                                                                     Figure 1: 'Williams' pears removed for redevolpment

Remove as many roots as possible

Old roots can harbour harmful levels of soil organisms that can reduce the performance of newly planted trees. Decaying roots can be toxic to young trees and can be a source of nematodes and disease. It is important to remove trees when soil conditions are suitable for maximum removal of roots.

After tree removal tree lines should be ripped to 35-40cm to remove any remaining roots. If practical all root pieces longer than 30-40cm and larger than 4-5cm in diameter should be removed.

Do not burn old trees on land to be replanted

Heat generated by burning old trees can adversely affect soil micro-organisms and nutrient availability under the heap. For orchard uniformity it is best to burn the trees off the replant site. If trees must be burnt on site, several small heaps are better than one large one.

Avoid erosion problems on steep slopes

On steep slopes tree removal can cause soil erosions. Growers may need to look at measures to minimise the speed of water running down the block. A cover crop should be planted if land is going to be left fallow for a long period.  

Site and Soil Preparation 

This is the critical aspect of redeveloping an orchard. The greater the attention to detail in this phase the greater the long-term benefits.  

Weed control

Managing weeds before the planting of a pear block will help reduce the competitive pressure of weeds during young tree establishment. It is particularly important to control perennial weeds before planting as these are harder to manage in established blocks than in open ground. They will also compete with any cover crops or permanent sod sown. For information on weed control please visit the weed management page.

Ripping  

Ripping can improve soil aeration and drainage, reduce compaction problems and remove roots from previous orchard plantings (if needed). Ripping is best done when soil is dry.

Cultivate soil

Planting sites need to be well cultivated with friable soil. Cultivation can also unearth old roots in an existing orchard block.

Mark out new rows

It is important to minimise the number of new rows in old row positions.   

Considerable debate centres around which is the best row orientation. As a general guide all orchards should be planted with as close to a north-south row orientation as practical except where site constraints or operator safety prevent this occurring.

Fumigate if required

Fumigation is only one tool that can be used to prepare the site, often many of the cultural practices such as adjusting nutrition and soil structure can reduce the need to fumigate. 

If fumigation is required prepare the soil to the right tilth and ensure that there is adequate soil moisture (dry soils minimise the effectiveness of fumigation). Depending on the chemical used to fumigate soil covers may be needed. These covers can greatly increase erosion problems on steeper sites so install appropriate erosion minimisation actions, ie interceptor drains etc

Fumigation is most successful in warm moist soils with temperatures over 16°C – Autumn is preferred to spring as the chemical must be removed before planting can proceed.  Germinating quick sprouting vegetable seeds can be used as one test to check wether the chemical has been properly removed from the soil.

Even out the site if required

Some minor site earthworks may be needed to fill in low spots etc. If major earthworks are required this should be done prior to fumigation.  

Apply and incorporate fertilisers and soil ammendments

Prior to final soil preparation any fertilisers or soil ammendments such as gypsum or lime should be broadcast and incorporated at the recommended rates (determined by soil tests) to a depth of 15-20cm.

Mound treelines if necessary  

 Mounding of tree lines can improve drainage as well as increase the depth of topsoil available to trees. This is particularly important where there is an impermeable clay sub-soil. Mounding can be done through moving topsoil from the centre of the traaffic line to the treeline. Mounds should be about 0.5m high.

Final soil cultivation

The final soil cultivation should only be done when all fertiliser, soil amendments, mounds and grassed waterways (surface drainage) are in place. It should preferably be done on the day of planting. 

Establishment of cover crop or sod culture

 Cover crops or sod culture can help to stabilise the soil and provide a firm surface during planting. They also can reduce weed competition and provide organic matter to the soil. The choice of cover crop may depend on local conditions. Often ryegrass or a mix of ryegrass and clover are used. Before planting the tree line will need to be sprayed to ensure the cover crop doesn't compete with newly established trees.

Installation of support systems and irrigation

It is important that support systems and and irrigation are installed before planting or as early as possible after planting.

Movement of young tree tops can damage tree roots so it is important that they can be secured to a support system. It is also important to minimise any water stress to rapidly growing young trees through irrigation.   

Acknowledgements to Paul James (Rural Solutions SA)  for providing much of this information

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Further Information

Growers should always seek local advice when planning to develop an orchard site. There may be locally specific issues that need to be considered in terms of climate, soil type and nutritional status. 

These resources may be useful for growers. However they are intended as an information source only. Any specific chemical or other management recommendations may be outdated or irrelevant for Australian conditions and growers should seek local advice.

Please note: By electing to visit sites linking from this page you will be leaving the intensivepear.com website.

Australian Resources

• Successfully Replanting Orchards, Five Easy Steps, A Best Practice Guide by Paul James. This book is available by contacting the Apple and Pear Growers Association of South Australia ( This e-mail address is being protected from spam bots, you need JavaScript enabled to view it ) 

International Resources

• Planting and care of young orchards - Washinton State University Publication (external link).