Sustainable Nutrition, established by Sjef Lamers in 1992, is an independent consultancy firm specialising in advice on the nutritional aspects of a comprehensive range of crops in horticulture and agriculture. We help growers with the optimal production of crops on a sustainable basis. Sonja Lamers has been in the business since 1995 and looks after the administration and accounting side.
Our areas of expertise include soil fertility, plant nutrient and research into specific issues. We have extensive experience in optimising nutrition for grapes, olives, nuts, berries, truffles and many other crops.
Qualifications
Sjef Lamers has extensive experience and qualifications which underpin his work, including:

- Bachelor of Forestry Science HBCS Velp (NL) (College for Forestry and Land and Water Management) Subjects: Soil Science, Industrial Economy, Workstudy, Silviculture, Forest Planning, Harvesting
- Post Graduate Diploma in Agriculture HLS Dordrecht (NL) (Agricultural College) Subjects: Pastoral and Arable Agriculture; Marketing; AgriBusiness
- Massey University, Palmerston North, New Zealand Subjects: Natural Resource and Environmental Economics; Management Accounting; Advanced Management Accounting; Strategic Management
- Study tours to the USA and The Netherlands on nutrition management and soil rehabilitation management of polluted sites.
- Study tour to The Netherlands, Israel, Greece, Italy and Australia on acid soil issues, including heavy metal toxicity, olive growing; nutrition management of grapes and olives; plant-soil interactions and irrigation. Attended the 3rd International Symposium on Olive growing in Chania, Crete.
- Study tour to the USA East Coast on establishment, management and nutrition of cranberries.
Achievements
- studied and proposed management of sodic sub soils for grapes
- reviewed the influence of grapevine nutrition on wine making and wine quality
- investigated and implemented olive and cranberry nutrition management
- researched amelioration of aluminium toxicity on plant roots