We have got a 2 acre property covered in Kikuyu grass. Being close to spring now we want to establish a big vegetable patch that is currently covered in Kikuyu. What is the best way to get rid of it with the least physical impact and without harming the soil for the vegetables? And how should we prepare the soil?
Thanks for your help!
Far South Coast, Australia
Getting rid of large areas of Kikuyu will prove somewhat of a challenge. To choose the best approach for your piece of land, an overview of organic weed management will help you make decisions. There are a range of organic weed control methods which you can try. Check out the following website for an indepth look at organic weed control in general.
The article, Principles of sustainable weed management for cropland describes weeds as "unwanted guests in agricultural fields, "invited in" by management decisions that defy nature’s principles. Managing croplands in tune with nature’s design makes for fewer and less-costly weed problems".
To control Kikuyu grass it is important to prevent it from spreading to new areas. It is spread both from seed and stem sections. Mowing and cultivation equipment is often the means by which it spreads, so these should be cleaned. Contaminated soil and planting stock is another means of transplanting. Ensuring planted areas are healthy will help resist Kikuyu invasion. Along with prevention, hand removal and spot killing of solitary plants are used. Cultivation or hand-hoeing, although possible, is generally not advised because it breaks rhizomes and transplants them to new areas. Mulching with strong landscape fabric can work if it is overlapped and no light is allowed to penetrate to the soil but synthetic mulches such as weed matting (woven black plastic) and polythene film, may be allowable but discouraged under organic certification standards.
Lemon grass can be grown in closely planted rows to form a living barrier against Kikuyu.
Also see the following links:
The Answerfile: Kikuyu
Organic Weed Management Project methods used by Australian herb and vegetable growers.
How to convert to organics or Biodynamics: Biological Farmers of Australia Co-op
About Kikuyu - Grasses for subtropics