What are organic vegetables? Standard steps for organic vegetable production

1. A brief history of organic farming

Origins of 20th-century organic farming

The organic concept was developed between the 1920s and 1940s, before synthetic agrochemicals became widespread. Pioneers focused on improving traditional farming systems, using soil humus and on-farm ecological balance as the foundation.

As high-yielding varieties, mechanization, and agrochemicals developed during the Green Revolution, organic farming continued to maintain methods such as composting, crop rotation, and green manuring. Since the 1990s, awareness among producers and consumers has surged, alongside advances in biological pest management and more efficient farming systems.

2. Organic standards

Organic producers must comply with standards that clearly define what is allowed and what is prohibited in farming. PGS standards guide the protection of biodiversity, the establishment of buffer zones, the prevention of contamination from parallel production, seed selection, and input management.

• Maintain biodiversity in the fields and surrounding habitats.
• Establish a buffer zone of at least 1 meter and expand it when there is a high risk of contamination.
• Store and transport organic products separately and label them clearly.
• Prioritize organic seeds; do not use genetically modified materials.
• Inspect all materials against the PGS-approved input list.
• Register production land, keep records, and participate in annual inspections to get certified.

3. Building soil fertility

Healthy soil creates healthy plants. Soil fertility and structure are improved using compost, hot-composted animal manure, green manure crops, rock minerals, microbial fertilizers, and liquid fertilizers. Chemical fertilizers are not permitted due to their negative impact on soil organisms and soil structure.

Compost should be mixed with about 50% green materials, 25-30% straw or rice husks, and 20-25% animal manure. The compost pile should be about 1.5 m high, sheltered from rain, temperature-monitored, turned after two weeks, and turned again after three weeks to maintain the decomposition process.

• All animal manure must be hot-composted before applying to the soil.
• A good compost pile reaches 50-60°C within 2-3 days and maintains it for 1-2 weeks.
• Plant legumes, cover crops, and green manure crops to replenish organic matter, fix nitrogen, and protect the soil.
• Natural minerals, bio-fertilizers, and liquid fertilizers are only used as supplements and cannot replace compost and green manure crops.

4. Soil and water management

Plan ahead before production, allowing about two weeks between applying compost and planting. Reduce the frequency and depth of tillage, avoid tilling when the soil is too wet, build appropriate beds for drainage, and avoid stepping on the bed surfaces.

Mulching the soil with straw or plant residues helps reduce erosion, prevent soil compaction, add organic matter, and retain moisture. During dry spells, clean and uncontaminated water must be used for irrigation.

• Keep canopies close together and mulch between rows when materials are available.
• Weed on sunny days; do not use herbicides.
• Rotate crops with strong weed-competing ability before sensitive crops.
• Apply fertilizer close to the plants rather than broadcasting it across the whole bed.

5. Crop rotation

Successive planting of different crops in the same field helps reduce the risk of nutrient depletion and limits pathogen buildup. Deep-rooted crops should be alternated with shallow-rooted ones, tall crops with quick cover crops, and heavy feeders with light feeders.

The five-group vegetable crop rotation formula dedicates about 20% of the area to green manure crops at one stage in the seasonal cycle, allowing the soil time to restore fertility for the subsequent crops.

6. Pest and disease management

The basic principle is that healthy plants have better resistance. Combine field sanitation, pruning, crop rotation, mixed cropping, trap cropping, good soil preparation, and creating a favorable environment for natural enemies. Only use botanical or biological pesticides when preventive measures are not sufficiently effective.

• Regularly inspect fields to monitor pests and natural enemies.
• Creates shelters for spiders, praying mantises, ladybugs, birds, and beneficial insects.
• Clear away diseased leaves and crop residues to reduce sources of infection.
• Clearly record the date, type, and quantity of inputs used in the production log.
• Use dedicated spraying equipment for organic areas.

7. Harvesting and post-harvest storage

Harvest vegetables while still young and handle them carefully to prevent damage and rot. Organic vegetables must be stored and transported separately from conventional produce, clearly labeled, and kept free from substances or packaging that previously held prohibited inputs.

8. Tools and equipment

Sprayers must only be used for organic production; conventional production areas must have separate sprayers. Hoes and shared tools must be washed clean before being brought into organic fields.