To prepare tea manure, soak 3A sack of dried cow or horse manure in a 3A plastic drum (200-L capacity) of water.
Soak for 5-7 days with frequent stirring. Dilute tea manure in up to 20 parts water and spray on the leaves at 1-2 weeks interval. To prepare FPJ, mix three parts chopped plant shoots or banana trunk with one part raw sugar or molasses. Ferment mixture for 5-7 days. Dilute 1 part FPJ to 20-40 parts water and drench on the plots or use as foliar fertilizer.
Carrot needs a lot of moisture during the first 30 days of growth. Irregular watering leads to cracking and forking. Water every 5-7 days or as needed. Mulch with dried grasses or rice straw to minimize weed growth and moisture loss.
Herbicides such as linuron may be used. Spray just after sowing to control broad-leaf weeds. Subsequent hand weeding is done in time with thinning and hilling up.
Thinning and Hilling Up
Thinning is done to provide enough space to the growing roots. Start thinning at 30 days after sowing, at a spacing of 10 cm between plants. Hill up immediately after thinning to cover the growing roots, control weeds, and cover the sidedressed fertilizer. Second weeding and hilling up is done 45 days after the first weeding.
Pest and Disease Management
Carrot is generally tolerant to pests and diseases, making it easy to grow organically. However, there are also a number of pest and disease problems:
Pests and Recommendations:
- Cutworm – Spray with biological pesticides such as Bacillus thuringiensis (Bt) and Nuclear Polyhedrosis Virus (NPV) following the recommended rates. If needed, spray with insecticides like fipronil, fenvalerate, permethrin, or other registered chemicals following the recommended rates.
- Armyworm – Spray with Bt following the recommended rates. Maintain populations of ground beetles and tachinid flies. Spread ash baits along the field borders. If needed, spray recommended pesticides such as carbaryl, fenvalerate, or malathion following the recommended rates.
- Mole cricket – Use biological sprays such as Bt and NPV. Spray with pesticides such as diazinon following the recommended rates. Use carbofuran following the recommended rates, as a last resort.
- Slugs – Spread rice hull ash or slug pellets around the plots just to cover the soil.
- Aphids – Spray with hot pepper extract (100 g macerated hot
pepper/16 L water). If needed, spray carbaryl or malathion following the recommended rates.
Diseases and Recommendations:
- Powdery mildew – Spray sulfur-based fungicides or mancozeb following the recommended rates. Bacterial soft rot Avoid injury to the roots during harvest and remove infected roots.
- Root-knot – Practice crop rotation with non-host crops like corn. Plant marigold by broadcasting the seeds in between seasons. Plow under the marigold plants at land preparation. Marigold may also be intercropped along borders and alleys.
- Alternaria blight – Use resistant or tolerant varieties such as Terracotta and S-505. If infection is severe, spray appropriate fungicides such as mancozeb and chlorothalonil following the recommended rates.
Carrot can be harvested from 90 to 120 days after emergence depending on variety and location. Loosen the soil using a spading fork then pull the carrot roots carefully. Haul the roots to the packinghouse immediately after harvest. Yields are usually 20-30 t/ha under favorable conditions and good management.
Cut the leaves 5-8 cm from the shoulder. Wash the roots and air-dry. Sort and classify according to size and appearance. Roots that are cracked, deformed, and forked are considered non-marketable, but can still be cooked or processed.
Cost and Return Analysis Per Hectare
Pack the marketable roots in bamboo baskets, plastic crates, plastic sacks, or polyethylene bags.
Carrot is sold either on a wholesale, contract, auction, or consignment basis. In Benguet, carrot is usually sold unsorted and unwashed as ‘buhos’ or ‘palaspas’ by growers.
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