Here is my suggestion to improve the Ulluco article. I added some sentences where there was already information and added the subchapters nutritional value, cultivation and pests and diseases.
Sentences I added in the introduction part:
Ulluco is an erect and compact plant which is 20-50 cm high. Its tubers vary in shape and color. The tubers can take every shape between spherical and cylindrical. The colors are manifold and can be white, light green, pink, orange and purple. 
The name Ulluco stems from the Quechua word ulluko, where ullu means male organ.
Ulluco is known to contain high levels of protein, calcium, and carotene. The tuber is also a good source of carbohydrates. Fresh ulluco contains about 85% water, 15% sugars and starches, 1-2% proteins, wherease the protein content varies considerably. Up to 15% of proteins in dry weight have been reported. The unusually high vitamin C content of Ulluco (23mg/100g fresh weight) has also to be mentioned.
Ulluco is cultivated at the high altitudes (2'400-4'000 m) of the Andes from Venezuela to Argentina, where daylengths don't exceed 10-13.5 hours. Ulluco is drought and cold resistant and well adapted to the predominant marginal soils. But the plant is also grown at sea level in Canada, England and Finland. 
The crop is cultivated in a similar way to potato, oca and mashua. Parts of the tuber or the shoot can be planted directly into the soil. No hormons or other treatments are necessary. A temperature of above 18 °C is ideal for the growth. The tubers are planted in furrows with row spacing of 80-100 cm and distance of 40-50 cm. The planting density is recommended to be 450-675 kg/ha depending on the size of the tubers. Ulluco is normally planted during the rainy season and followed by potato as ullucos have a long vegetative period, which lasts between 5 to 8 months depending on the varieties and the elevation.  But ulluco can also be intercropped with potato, mashua, quinoa or beans. It is not common to use fertilizer. Farmers however, sometimes add manure and harvest leftovers to improve the fertility of the soils. Between 6 and 12 t/ha are seen as a good dose.  The yield average is between 5 and 9 t/ha. 
Pests and diseases
Ulluco has few pest and disease problems. But it has been shown that the tubers are generally infected by viruses which decreases yield. Potential yield of virus free plants could be 30-50% more. 
- Ulluco tuberosus, Ecocrop
- Fuccillo, D., Sears, L. & Stapleton, P. (eds.) Biodiversity in Trust, 1997, Cambridge University Press
- Lost Crops of the Incas: Little-Known Plants of the Andes with Promise for Worldwide Cultivation, 1989, National Academies Press, Washington D.C.
- Vimos, Carlos N., Nieto, Carlos C., Rivera, Marco M. El Melloco, Características, técnicas de cultivo y potencial en Ecuador, accessed March 30, 2011.
[[Category:Caryophyllales]] [[Category:Crops originating from Bolivia]] [[Category:Crops originating from Colombia]] [[Category:Crops originating from Ecuador]] [[Category:Crops originating from Peru]] [[Category:Root vegetables]] [[Category:Leaf vegetables]] [[ay:Ulluku]] [[cs:Melok hlíznatý]] [[de:Olluco]] [[es:Ullucus tuberosus]] [[fr:Ulluco]] [[it:Ullucus tuberosus]] [[lt:Gumbinis uliukas]] [[pt:Ullucus]] [[qu:Ulluku]] [[ru:Уллюко клубненосный]] [[fi:Ulluko]] Bauerf (talk) 09:42, 4 May 2011 (UTC)