The quality and shelf life of Early Short and Intermediate Day onions are key points in Zimbabwe’s onion production activities. Zimbabwean farmers and fresh markets are now focussing more on the cultivation of a higher product quality, and above all, a longer shelf-life and drying onion variety. In order to focus on these key points, Prime Seed has brought in Hybrid F1 variety called Regent Onion.
This onion is a light-brown skinned hybrid onion variety. The bulbs are globe shaped, very firm and have quite good storage ability, particularly for such an early variety. The yield potential of Regent is extremely high. The flavour of the onion is very sweet and mild. In the field it has shown to be strong against Downy Mildew.
Regent is recommended for planting during mid-late autumn and cool weather i.e. autumn and winter so that they are lifted in early summer. Cool conditions with long days are normally essential for production of onions and warmer weather is required when the crop is harvested. Temperature plays a significant role in initiating and influencing the rate of bulbing. Fluctuating weather conditions can influence flowering of onions although they normally flower in the second year. It also causes bolting but low temperatures will inhibit bolting. The maturity is 20-24 weeks after seeding, depending on location, seasonal factors and planting date.
- Onions prefer lighter soils although they can be grown on a wide range of soils.
- Onions have a relatively shallow root system to depth of about 200mm to soil depth of 300mm.
- Heavy clay soils are difficult to work with and cause serious problems at harvest.
- Soil PH of 5.5-6.5 is optimum as at low PH.
Fertilizer and Manure Application
- For fertilization a general recommendation of Compound C (6:17:15) should be applied at the rate of 1 000kg/ha.
- Organic manure of 50 tons per hectare can be applied and calcium nitrate of 30kg per hectare starting at 3 weeks after transplanting, then same quantity at 5weeks, 7weeks and 9 weeks up until seventh or eighth leaf stage.
- Too much of manure and nitrogen may cause numerous problems such as late ripening of the crop, development of large, thick-necked bulbs which makes it a problem during storage and bolting will be encouraged.
600 000 to 800 000 plants per hectare. Plant beds of 1.2m-1.6m beds centre to centre. 5 to 8 rows per bed 20cm apart and seeds 5cm to 10cm apart.
After transplanting seedlings should be watered daily until plants stand out. A good onion crop requires 600mm-700mm of irrigation.
Prime Crop Protection
- Nematodes farmers can apply Solvigo 108SC
- Soil Pests and Cutworm can be controlled by Actara and Karate Zeon 5CS respectively
- Thrips and White Tip can be controlled by Ampligo and Revus respectively.
- Purple blotch (alternaria) and Neck Rot both can be controlled by Amistar Top 325SC
All the above chemistry available in all Prime Seed shops.
In Zimbabwe, Onion farmers normally start their seedbeds annually in early March, so farmers are being reminded that the onion season has come and should kick start it with the REGENT.