How is companion planting necessary for organic farming ?

Question

How is companion planting necessary for organic farming ?

Answer 1

Some plants do better for a number of reasons. Mixing plants is closer to nature as monocultures don't exist to any great extent. It is a good way to naturally fool a pest and keep their spread minimized. Mixing plants that make natural chemicals to reduce pests like some forms of marigold and the pyrethrin source Chrysanthemum cinerariaefolium. Planting squashes and pumpkins with corn provides a ground cover to limit weeds and herbicides and is a good way to manage orchards. Also light vines with corn use the corn for some support. These are just a few examples of why one would do companion planting but as to the possible combinations, they are endless. Look at it in terms of nature. Life will occupy a certain niche and we are always amazed to find how life adapts. Just have a niche and a plant, or animal, will fill it. That niche can be the shade left by trees and tall plants, the spaces between rows that would get weedy, or the spaces between plants also. One has to research and take care not to cause a problem though by over use and competition, by blocking light or limiting air flow for ventilation and drying vegetation. And root competition though not seen also needs consideration as do feeding needs and water. Can't plant prickly pear and watercress, and tomatoes will pull down corn where pea vines won't. Growing lettuce in the shade of corn in the heat of a season might seem OK but one needs a higher nitrogen component and if fed too much phosphorus and potassium it will bolt with tiny leaf.

I'll stop before I write the whole book, I have a habit of that when I warm to a topic.

Answer 2

There are seven basic reasons that companion planting is beneficial for organic farming. (1) Trap Cropping: A neighboring crop is more attractive to pests and serves to distract them from the main crop.  (2) Symbiotic Nitrogen Fixation: Legumes have the ability to fix atmospheric nitrogen for their own use and for the benefit of neighboring plants (beans inter-planted with corn). 3. Biochemical Pest Suppression. Some plants exude chemicals from roots or aerial parts that suppress or repel pests and protect neighboring plants. The African marigold, for example, releases a nematode repellent—making it a good companion for a number of garden crops. 4. Physical Spacial Interactions. For example, tall-growing, sun-loving plants may share space with lower-growing, shade-tolerant species, resulting in higher total yields from the land. Spatial interaction can also yield pest control benefits. 5. Nurse Cropping: Tall or dense-canopied plants may protect more vulnerable species through shading or by providing a windbreak.  In many instances, nurse cropping is simply another form of physical-spatial interaction. 6. Beneficial Habitats: The benefit is derived when companion plants provide a desirable environment for beneficial insects and other arthropods—especially those predatory and parasitic species which help to keep pest populations in check. .

7. Security Through Diversity: A more general mixing of various crops and varieties provides a degree of security to the grower. If pests or adverse conditions reduce or destroy a single crop, others remain to produce some level of yield.

Answer 3

It can reduce pests