Organic Crop Production Nursery and field management biointensive

Organic Crop Production: Nursery and field management /bio-intensive tillage practices/pre and post harvest handling of organic produce

Outline 1. Objective 2. Definition 3. Site selection and layout 4. Types of nurseries 5. Preparation of a nursery 6. Good crop establishment 7. bio‐intensive tillage practices 8. pre and post harvest handling of organic produce 9. Questions for discussion 10. List of references

objective 1. Apply the principles and practices of organic crop production in: • Nursery and field management • Soil cultivation and tillage 2. Apply bio‐intensive tillage practices 3. Properly handle organic produce during and after harvesting to maintain organic qualities of the produce

Definition • A nursery is an area of land dedicated to raising seedlings • Nurseries are prepared for both vegetables and trees • The crops usually raised in nurseries are mainly those with very small seeds

Benefits of having a nursery • Enable plants to grow strong before transplanting them • Protect young seedlings from damage by livestock and adverse weather effects • Saves time, space and other inputs

Site selection and layout Site selection criteria: ‐ • microclimate‐ temperature, precipitation , wind • Soil‐ soil fertility‐ soil nutrients, soil moisture, soil texture, depth, soil Ph, soil erosion potential, compaction; permeability, tilth • Water‐ quality and quantity of water adequate. In most nurseries, irrigation is necessary: ‐ irrigation water should be free from contamination from weed seeds and mineral content • Topography: The area for nursery should be level or nearly level, a slight slope is beneficial for better surface drainage

(Continue) • Previous land use: past practices that have altered soil acidity or caused toxic chemicals to accumulate will be detrimental to growing seedlings; what was the previous cropping schedule? ; were diseases problems associated with any particular crop and protection measures taken; examine current vegetation for root and foliar diseases; site should be free from annual and perennial weeds and weed seeds; select a weed free site

Types of nurseries 1. Raised nursery For use in high rainfall areas Advantages: • Easy to make • Able to raise enough health seedlings • No danger of water logging Disadvantages: • Losses water very fast during the dry period

Continue 2. Sunken nursery Used in drier areas Advantages: Less water is used to raise the seedlings because you concentrate water into the bed Disadvantage: There is danger of water logging leading to diseases

(Continue) 3. Movable nursery Seedlings are raised in wooden flat, boxes and plastic containers if land is scarce Advantages • Can move seedlings anywhere you want to plant • Less damage of seedling during transplanting • The seedlings can be moved to a safer place when there is a lot of rains or animal damage • Have less pests and diseases because they are movable from one place of unfavorable to favorable conditions

(Continue) Disadvantages Large scale enterprises are difficulty as this method is expensive Setting a nursery: considerations: • Availability of water • Protection from wind • Close to shade • Place where there is no water logging

Management of a nursery • After sowing water the bed using a watering can. Avoid over watering, it may cause compaction. The best time to water is early morning and late afternoon when the rate of evaporation is low • During hot weather construct a simple shed over the nursery • If there is thick germination, thin to avoid weak seedlings. Remove shading gradually to get the seedlings used to full sunshine • Weed the nursery to keep it free from competition and plants that may host pests and diseases • You may need to use organic inputs in case of diseases and pests

Soil cultivation and tillage Soil cultivation includes all mechanical measures to loosen, turn or mix the soil, such as ploughing, tilling, digging, hoeing and harrowing. Careful soil cultivation can improve the soil’ s capacity to retain water, its aeration, capacity of infiltration, warming up and evaporation. But soil cultivation can also harm the soil fertility as it accelerates erosion and the decomposition of humus. Depending on the cropping system and the soil type, appropriate soil cultivation patterns must be developed.

(Continue) Reasons for cultivating the soil: ‐ • Loosen the soil to facilitate the penetration of plant roots • Improve the aeration (oxygen and nitrogen from the air) • Encourage the activity of the soil organisms • Increase the infiltration of water • Reduce evaporation • Destroy or control weeds and soil pests • Incorporate crop residues and manures into the soil • Prepare the site for seeds and seedlings • Repair soil compaction caused by previous activities

(Continue) Types of soil cultivation: Different cultivation practices are implemented during different stages of the cropping cycle: after harvesting, before sowing and planting crop stands 1. Post harvest: • Crop residues of the previous crop are incorporated into the soil before the preparing the seed bed for the next crop • Crop residues, green manure crops and farmyard manure should be worked only into the topsoil layer (15‐ 20 cm) as decomposition in deeper soil layers is incomplete, producing growth inhibiting substances which can harm the next crop

(Continue) 2. Primary tillage: Soil cultivation should achieve a flat turning of the top soil and a loosening of the medium deep soil. Deep turning the soil cultivation mixes the soil layers, harms soil organisms and disturbs the natural structure of the soil 3. Seedbed preparation Before sowing or planting soil cultivation is done. It provides loose soil and it eliminates the young seedlings 4. In-between the crop Shallow soil cultivation helps to: ‐ • suppress the weeds; • enhances the aeration of the soil and at the dame time reduces the evaporation of the soil moisture form the deep soil layers • Stimulates the decomposition of organic matter, therefore making it available • Farmers can do Minimum (Organic Manure, Mulch, cover crops) and zero tillage (mulch residues)

Bio-intensive tillage practices

Bio‐intensive tillage practices Definition: Biointensive agriculture is an organic agricultural system that focuses on achieving maximum yields from a minimum area of land, while simultaneously increasing biodiversity and sustaining the fertility of the soil. The goal of the method is long term sustainability on a closed system basis. It is particularly effective for backyard gardeners and smallholder farmers in developing countries, and also has been used successfully on small‐scale commercial farms.

(Continue) Bio‐intensive methods can enable small‐scale farms and farmers to significantly increase food production and income, utilize predominantly local, renewable resources and decrease expense and energy inputs while building fertile topsoil at a rate 60 times faster than in nature

Bio‐intensive practices Bio‐intensive approaches include: • Double digging • Raised Beds • Bio‐intensive Planting eg. Five or nine maize in a hole • Companion Planting • Mandala gardens • Mazimbuko gardens • Companion cropping • Zero tillage • Minimu tillage • Etc

Raised beds are made by adding manures to the farm and digging about ½ m below the ground Advantages: • Raised beds are easy to make • There is a good crop on raised beds during their first season • There is no water logging as compared to double digging during long rains season

Double digging • Double dug planting beds build up a deep layer of loose, well‐ composted topsoil, which allows intensive growing of vegetable crops • Deep, well composted top soil allows closer spacing of plants than normal and continuous growing of crops where watering or irrigation is possible • Double dug beds close to the homestead can provide a family with fresh vegetables throughout the year • It is better to have a number of double dug beds(5‐ 10) in order to plan your rotation of crops well • A double dug bed should be planted with the plants closer than normal because the roots spread downwards much more easily

(Continue) • Plants which are closely spaced also keep down the growth of weeds • The plants leaves also protect the soil from sun, wind and rain • Always weed and harvest the produce while standing on the path

(Continue) • How do you make double dug planting beds? • What are the advantages of using double dug beds? • Disadvantages of using double dug beds

Mandala gardens • This is a double dug bed prepared in a circular manner with an inlet for water preferably harvested from the house roof behind the kitchen • The beds should be approximately 1. 5 M wide with a central pit about 1 M in diameter and one meter in depth (central pit used for water collection and disposing of weeds) • Planting are then grown in several lines all around • Water is collected and retained in the mandala rings • This is best for dry regions or dry seasons where crops/vegetables can remain green for a long time without necessarily watering

Mandala gardens • What are the advantages of using mandala garden? • What are the disadvantages of using mandala garden? • How can mandala garden be made?

Organic Production Systems: Harvest and Postharvest Handling in Organic Farming Systems • Approved Chemicals for Use in Organic Postharvest Systems (Codex guidelines, 1999) • Influence of Pre‐harvest Factors on Postharvest Quality ‐soil factors ‐nitrogen phosphorous and potassium ‐calcium ‐soil texture ‐irrigation ‐Insect pests and diseases ‐varieties

References 1. FAO (1999). Guidelines for production, processing, labeling and marketing of organically produced foods 2. FAO (2015). Training manual for production for organic crop productios

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