There is now a second product containing maleic hydrazide, besides the growth regulator Itcan: Fazor. Itcan and Fazor are used as growth regulators on the potatoes at least three to four weeks before harvest.
When Fazor can be used depends on the size of the spuds: for small varieties 80% of the spuds has to have a minimum size of 25 to 30 mm, for bigger varieties this is 35 to 40 mm. From this size on the cell division in the spuds is closed, after this there is only cell extension. From this moment on there will be no loss of crops due to the use of the product.
When Fazor can be used depends on the size of the spuds: for small varieties 80% of the spuds has to have a minimum size of 25 to 30 mm, for bigger varieties this is 35 to 40 mm. From this size on the cell division in the spuds is closed, after this there is only cell extension. From this moment on there will be no loss of crops due to the use of the product.
It is recommended only to use a growth regulator at temperatures of 25 ºC. During very warm, dry weather the application should take place in the morning. The potatoes should not be watered for the next 12 to 24 hours, so rain forecasts should be paid attention to. The producers recommend making a choice between Itcan or Fazor and not to use both products at the same time. The waiting period is 21 days. Use on seeding potatoes not permitted.
To make the product work, the potatoes plants need to have green leaves for at least another eight days. The active ingredient needs this time to reach the spuds through the sap stream. When the sap stream is limited, due to high temperatures or advanced ripeness for instance, there is no full effect. This is why it's important that you determine beforehand whether or not application is useful, by looking at conditions such as the size of the spuds, the state of the plants and the weather conditions.