Powdery is a collective term for a number powdery shading agents resp. Spuitfix, Whitefix and Shadefix. These products are all produced from pure chalk with the addition of a binder (starch). The amount of binder that is added to the chalk determines the lifetime.
Theory
Powdery shading agents are very straightforward. Growers that choose to work with Fixen can only shade in one shading percentage, which doesn’t always live up to the crops needs.
The figure below shows how the light is screened with a Fixen product. It is clearly seen that with Fixen only the intensity of the light is decreased.

These lifetimes can be affected by unusual weather conditions such as excessive rainfall or hail.
 

To increase the durability of Shadefix, Transfix can be added, but only on the first layer. In practice a dosage of 15 liters of Transfix per 250 kg Shadefix should be maintained.

Application
When applying Fixen the following guidelines should followed:

• Follow the manual as printed on the bag. 
• First completely dissolve 75% of the total dosage in water and after that add the remaining 25%. 
• Apply the Fixen on a dry, degreased and clean surface. 
• Ensure at least 4 hours of drying time

Removal
Spuitfix wears off from the deck within a few showers.

Shadefix and Whitefix can be removed from the deck with Greenhouse Clean CC or by brushing it off from the deck. When using Greenhouse Clean CC a dosage of 4 cans per hectare should be maintained (dissolved in 1500 liters of water). After a shower or by spraying off with clean water, the Fixen should have been washed off. With plastic greenhouses it is obligatory that after using Greenhouse Clean CC the greenhouse is sprayed with clean water.