Research and Extentions

Alternative Crops

Fathen and Relatives - article on fathen (the weed) and its relatives

Fusion Vegetables - article on Asian vegetables

Golden Linseed Trial - BHU trial on Winter Linseed contact for information on being a linseed or winter linseed crop.

Linseed Stripper Simulation - BHU trial looking at the use of a stripper front on harvesting linseed (brown and golden varieties). The technique allows harvesting before loss from birds. Trial simulates the stripper front by hand. Contact for information on being a linseed or winter linseed crop.

Annual Reports

Here you can access the BHU Annual Reports including coverage of much of the research activity. The first annual report is to the end of March 2003.

BHU Annual Report March 2003 MS Word 476kb

The second (half year) report is to the end of August 2003

BHU half year Report August 2003 MS Word 73kb

Subsequent reports will come out for July of each year.

BHU Annual Report July 2004 MS Word 549kb



Corn, Bean Squash - BHU experiment on corn, bean and squash intercropping

Multipurpose Shelterbelts - article

The Role of New Zealand Native Plants - short article on use of NZ natives in agricultural systems.


[Also see the Soil section in BHU information pages for experiments and articles related to composting]

Below is a table of C:N ratios and other relevant data for working out desirable mixtures of compost material. Composting is very forgiving and sawdust by itself eventually rots after several years and lawn clippings by themselves although causing smell and fly problems will turn into first something a bit like very poor silage and eventually humus. Of course we want to have something in between.

Too much nitrogen leads to potential anaerobic (lack of oxygen) conditions, odour problems and loss of nitrogen.

Too little nitrogen causes a slower than needed process and can mean insufficient heat to kill weeds and weed seeds and to control plant diseases.

Too much compacted material such as grass clippings can cause anaerobic conditions and odour problems.

Too loose a compost may slow the composting and mean insufficient heat. This can be overcome to some extent by compacting the material while building the heap.

Use the table below to help balance out ingredients for your compost heap. For an efficient heap the aim is for an overall C:N ratio of 25 to 30 (30 is the balance that most microorganisms have between carbon for energy and nitrogen for protein - 25 makes for a better functioning heap). To work out the combined C:N ratio, use the average of the C:N ratios e.g. 5 parts dairy manure to 1 part wheat straw = (13 X 5 + 125)/6 = 32 which is close to ideal. REMEMBER C:N RATIOS ARE BY WEIGHT SO THE PARTS ARE BY WEIGHT - TO CONVERT TO VOLUME MEASURE SOME OUT OR USE THE ROUGH GUIDES BELOW.

NO NEED TO BE EXACT, BELOW ARE JUST ROUGH GUIDES AND COMPOSTING IS FORGIVING (though commercial compost needs to be a bit more fastidious)

C:N Ratio weight/weight
N% fresh
Bulk Density (kg/m3)

Moisture Content (%)

Apple Pulp 12 2.0 3000 65%
Corn Cobs 60 to 130 0.5 1200 12%
Maize/Corn Stalks 70 0.6 70 12%
Fruit Waste 40 0.2 3000 85%
Blood Meal 3.5 10 large range large range
Fish processig sludge 5.3 3.5 large range 95%
Abattoir Waste 3 5 large range large range
Paunch 25 1.0 3000 85%
Chicken Manure - broilers 14 2.0 2800 30%
Chicken Manure - laying 6 5.8 3000 40%
Chicken Litter (laying) 10 2.5 2500 30%
Horse Manure 30 1.0 2800 70%
Dairy Manure 13 1.8 3000 85%
Sheep Manure 16 1.4 2800 70%
Pig Manure 14 1.8 3000 80%
Kitchen Waste 15 2 3000 70%
Vegetable Scraps 20 2.7 3000 85%
Maize Silage 40 1.0 3000 65%
Hay 25 1.8 400 10%
Lucerne or Clover hay 16 2.2 400 10%
Straw - Oat 80 0.8 300 10%
Straw - Wheat 125 0.3 300 10%
Sawdust 450 0.08 500 15%
Weeds 20 0.3 4000 85%
Lawn Clippings (avoid herbicide treated) 20 0.3 5000 85%
Leaves 60 0.4 3000 40%


Conversion Planning - article on planning for conversion of a farm to organic agriculture

Cover Crops

Cover Crops General - article on cover crops

Cover Crops Introduction

Cover Crops More Details

Green Manures, Leys, Understorey Crops and Mulches - article

Visiting Speaker Ed Beste - notes from his 2003 talk at Lincoln University

Crop Protocols

The following crop protocols (doc format) summarise basic agronomic, organic production guidelines and provide examples of 'best organic practice' for a range of crops.

Effluent Management

Dairy Effluent Experiment - using Effective Microorganisms in conjunction with HortResearch

Farm Design

Substitutive vs System Approach - article on the difference between designing a system and coming in with a rescue and the role of pragmatism

Shelterbelt Design - article

General BHU

Sir Peter Elworthy - Article on Peter the past chairperson of the BHU Organics Trust obituary written by Tim Jenkins

Biological Agriculture - Article on the relatively new to New Zealand move towards Biological Farming

Letter for Support of the BHU - have you considered supporting the BHU?

Tree Crops Field Day - Article from when the Tree Crops Association visited the BHU

Growing Calendar


Livestock Diversity - article

Intensive Animal Production - article

Effect of EM on Lamb Growth - BHU expt

Animal Health

Mixed Cropping Strategy

Mixed Cropping - article written on mixed cropping strategies for Organic Linseed Growers Group

No Till

No Till Projects

Steam and fish fertilisers: A potential organic systemic herbicide?

Nutrients including Plant Nutrition

Potassium - article on Potassium with special relevance to organics

Selenium Fertiliser for Human Crops - article relevant to New Zealand

Trace Elements in Organics - article


The Pasture Phase - article on the pasture phase in Horticulture and Livestock

In The Clover - article on growing clover in the pasture

Pasture Foraging and Shelter Design - article

Pasture - general article

Plant Tissue Testing - taking herbage samples for maximising pasture productivity and caring for animal performance

Potting Media

Potting Media experiment including composting bark organically

Pests and Diseases

Black Spot (Venturia inaequalis) in Apples - article-

Carrot Rust Fly - article

Club Root of Brassicas - article

Conservation Biological Control of Crop Pests - article

Flower Power - article on flowers for beneficial biological control agents of crop pests

Potato Cyst Nematode - article

Sclerotinia sclerotiorum - article on this potentially devastating funal disease

Take All of Cereals - article

System Design for Pest and Disease Management - article

And if the System Fails - article on intervention in pest and disease management

Soil, Soil Fertility, Compost, Fertilisers, EM

Effective Microorganisms

A Fertile Soil - article about what is soil fertility

BHU Compost Analysis - Hill Laboratories analysis of BHU compost nutrient content

Approved and Restricted Fertiliser Materials for Organics - Annotated list and discussion

Biological Fertilisers - article

Compost and Farm Yard Manure - article about alternatives to fertiliser

Compost application experiment with Cabbage at BHU

Compost Potential - article on composting for the small farm

Composting Methods - article on how to compost on small farm scale

Composting - general article

General Composting Article - another composting article

Effect of Biological Fertilisers on Plant Growth - BHU experiment

Effect of Compost Rate on Vegetable Growth - BHU experiment

Enhancing Soil Biological Activity - article

Fertiliser programmes for Organics (intensive hort and mixed cropping) - article

Fineness of Fertiliser Particle Size Expt

Living Soil - gerneral article on soil biological activity

Manure and Composting Materials - nutrient composition and attributes

Measuring Soil Biological Activity - activity

Mulching Types - article

Mycorrhizae - article

Roots and Nutrient Uptake - article

Soil Diseases and Pests - article

Soil Fertility Programmes - article

Soil Fertility - article on definition of soil fertility

Soil Structure and Chemistry - article

Soil Testing Without Labs - article

Strategic Soil Testing - article

Sustainable Nutrient Budgets - article on judging how much fertiliser to use to be sustainable (and minimising needless losses)

The Rhizosphere - article on the microbial activity around plant roots

The Soil Web - article on soil biological activity and interactions between organisms

Weed Management

A Weed in Time Saves Nine - article on timely weeding

BioAgri Mulch Expt - experiment on using starch based mulch for vegetable crops

Stale and False Seedbeds - know the difference? know them at all?: these are important techniques for reducing crop weed burden

Weed Management - general article

end faq