Education:
BSc Agric (Soil Science) 1982 University of the Free State, South Africa
MSc Agric (Soil Science) 1990 University of the Free State, South Africa
PhD (Soil Science) 1998 University of the Free State, South Africa

Teaching:
Soil Science 142 – Applications in Soil Science
Soil Science 214 – Introduction to Soil Science
Soil Science 344 – Soil and Water Management
Soil Science 414 – Advanced Soil Physics
Soil Science 454 – Advanced Resource Management
Soil Science 772 – Specialized Soil Physics and Water Management

Research Interests:
I have thirty years of research experience in water management of dry land and irrigated agriculture and soil manipulation. This research has included the major cash crops viz. wheat, maize, sun flowers and grain sorghum and tropical and subtropical tree crops such as citrus, bananas, pineapples, guava, papaya, mango, avocado, macadamia, litchi, coffee and deciduous fruits, apples, pears and others like vineyards and table grapes. Water use of different crops has been studied with various soil water management and scheduling methods while soil manipulation research has assessed the effect of different soil preparation methods and pre-plant treatments on factors such as moisture retention, bulk density and root growth. I was also involved in a project were a new type of implement was developed for alleviating soil compaction in sandy soils of the Western Free State for crop production.


Research Projects:

The effect of winery wastewater on the hydraulic properties of selected soils

Long-term effect of conservation tillage practices on the water balance and selected soil physical properties of soils in the Southern Cape

The influence of soil tillage and crop rotation on plant available water in selected cropping systems at Langgewens

Evaluation of the Effect of an Orange Oil-Based Soil Ameliorant on Selected Soil Physical Properties

Evaluation of the Effects of an Orange Oil-Based Soil Ameliorant on Soil Water Management

Research into the most efficient deep soil preparation method over the long term for wine grapes in the Western Cape.

An investigation into the vigour and physiology of grapevines growing on and between “heuweltjies”.

Biochar amendment of infertile, sandy soil from the Cape Flats, South Africa.

Controlled deficit irrigation during different growth stages of apples and the influence of this on production and crop quality.

Controlled deficit irrigation of vineyards and its effect on production and wine quality
Influence of soil properties and water management on the medicinal properties of Mentha longifolia.

Investigation into the water use of wetlands of the Table Mountain Aquifer

Recent Publications:
Hoffman, J.E. (2004). Besproeiingskedulering gedurende tye van watertekorte. SA Vrugte Joernaal 3: 58-60.

Hoffman, J.E. (2003). Besproeiingskedulering. In: F. Koeglenberg (ed.) Besproeiings-ontwerphandleiding. LNR-ILI, Pretoria.

Stassen, P.J.C., Hoffman, J.E. and Grove, H.G. (2000).The relationship between tree dimensions, yield and nutritional requirements of mango. Acta Horticulturae 509: 347-351.

Professional Affiliations:
International Union of Soil Science (member)
South African Council for Natural Science Professions (member of the Professional Accreditation Committee)
Soil Science Society of South Africa (member)
South African Society for Horticultural Sciences (member)
South African Society for Oenology and Viticulture (member)
The Soil Science discussion group of Stellenbosch (member)