Plant Doctor Archive

Short on selenium

WE ARE constantly being told that our soils lack selenium. Could you please tell me what I can put on the vegetable garden to help build up the selenium?

SOILS in many parts of New Zealand contain relatively low levels of the trace element selenium. While this seems to have little, if any, effect on plant growth, the detrimental effect on animals, such as horses and cattle, that feed on plants grown on these soils is reasonably well documented. The effect on the New Zealand population is less clear.

Among other things, selenium is often referred to as a cancer-preventing nutrient in much the same way as antioxidants are. Some medical experts claim if you eat a balanced diet, including grains, meat and fish, you should receive an adequate daily amount of selenium. Other experts promote the regular use of selenium supplements.

It's important to note selenium is only required in our bodies in small amounts and you can get ill from taking too much.

For a wide range of information on the topic, type "selenium in New Zealand soil" into a Google internet search and you'll find impartial medical and scientific opinions, along with those from vested interests such as companies promoting health food supplements.

If you want to apply selenium to your vegetables, the simplest way is to use fertiliser based on fish waste - like Nature's Way Fish Emulsion - which usually list selenium among the trace elements on the label.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.