What is organic management?
The essence of organic horticulture is the achievement of high aesthetic and functional quality by enhancing natural processes, rather than by using substitutes for them.
The word organic comes from "organismic" meaning pertaining to the whole, thus it is a whole system or holistic approach. The approach emphasizes:- Recycling to conserve resources, and add organic matter to the soil.
- Diversification of habitat and species composition to give a good balance of nature for pest control, water conservation, etc.
- Feeding the soil: a healthy soil, it is argued, provides balanced nutrition and produces healthy, pest resistant plants.
- Using legumes to provide inputs of nitrogen.
The organic approach discourages the use of substitutes for natural materials and processes, such as synthetic or highly processed fertilizers, synthetic pesticides and genetically engineered organisms. Under strict organic management, these substitutes are prohibited. Even natural pesticides such as rotenone are discouraged; they are seen only as a last resort and necessary to use only during the transition to organic management when there are still many imbalances in the system.
Do's & Don'ts
Following are some of the do's and don'ts of organic turf management which follow from the general principles of the organic approach (the do's) and in the case of don'ts, from requirements for strict organic management. Some of the rationale for the "don'ts" are provided.
Fertility
Do's
- Use organic amendments to fertilize soil and composts to increase humus.
- Use grass species and mixtures that do not require high N.
- Use a mulch mower to recycle clippings in place.
- Encourage clover (fixes N2 gas from air, brings minerals up from depth).
- Assess N needs by greenness (visual), and % soil organic matter (lab test).
- Assess needs for P, K, and lime by soil tests in fall or spring.
Don'ts
- Do not use synthetic or processed fertilizer salts, especially highly soluble N fertilizers. They acidify soil, and in excess, cause rank growth which encourages pests.
- Do not use muriate of potash (KCl). The Cl ion is slightly toxic. Use potassium sulfate, sul-po-mag or other K source (wood ash, granite dust).
Weed Control
Do's
- Mow high (2.5 - 3.0 inches or 6 - 8 cm) to favor grasses over weeds.
- Use complex seed mixtures.
- Practice timely manual weeding followed by overseeding and mulching with compost.
- Overseed with clover to help discourage weed encroachment and diversify the sward.
Don'ts
- Do not use herbicides: they have sub-lethal effects on non-target plants which make them more susceptible; they kill clover; they add to the pesticide load on the environment.
Pest and Disease Control
Do's
- Focus on ensuring a healthy turf; it is more resistant to pests and diseases.
- Avoid over- or under-feeding grass with nutrients or water.
- Use complex mixtures.
- Dethatch and aerate as appropriate.
- Water regularly but not excessively, allow natural mid-summer dormancy or water regularly...not in between.
- Monitor pests.
- Use broad spectrum biological pesticides only when absolutely required.
Don'ts- Do not use any synthetic insecticides or fungicides: they kill beneficial organisms; they treat symptoms rather than causes; they add to the pesticide load in the environment.
- Do not create stress by mid-season fertilization and then not watering sufficiently to support the growth demand.
Source:
Greenfacts Special Reseach Edition, January 1998.
The Oaks Experiments on Organic Management of Turf
Summary of a Report by D.G. Patriquin, D.R. Reid, B.D. Walsh |
