What is the light loss under a rain cover?

Light is an important factor in fruit growing. It has everything to do with fruit colouring, but also for the vitamin C levels in fruit. All kinds of components of light are important in this.

Because light is so important in fruit, blocking light is also a sensitive issue. In this blog, I want to take a closer look at light loss under film canopies. With concrete measurement figures from practice, we will elaborate on the Powerflex foil system.

Light is both an advantage and a disadvantage

Light, as indicated, is an indispensable factor in fruit growing.

Many components of light are important and applicable to fruit. Such as the intensity of light, the colour of light and the amount of light the tree, plant or fruit receives.

Not enough light

When fruit gets too little light, it causes problems at harvest time. Fruit is less firm, sugar levels are lower and the colour is less. This can result in you selling less of your fruit, or selling it for a low price.

Sunburn

In recent years, the concept of sunburn damage has become increasingly common. In both hard and soft fruits. Sunburned apples, pears and cherries have become almost insurmountable.

All kinds of solutions are used to prevent this sunburn, such as sprinkling apple and pear plots. Or using hail nets in colours of grey and black.

With cherries, sprinkling is not an option, as the cherries may burst open due to the water. Making the product unsellable. Cherry growers are increasingly using protection systems such as foil covers for this purpose. Here, the foil protects the cherries from sunburn, but it can also block out necessary light.

Light under the Powerflex foil system

The film used in the Powerflex film system is woven film. This foil takes away a percentage of light. Below you can see the percentage of shade under the Powerflex foil system.

In this example, the canopy was built in 2015. The percentages show the light loss under the canopy. It can be seen that the film takes away more light the older it is.

This is because, due to movement over the years, the film develops smaller folds. These folds cause the film to become denser in that area. As a result, less light can get through.

Years with a lot of wind, therefore, cause the film to let less light through in the long run.

Besides causing folds, in practice, dirt is often left behind on the film. From rolling up and unrolling the system. But also from spraying crop protection products or otherwise.

Conclusion

A canopy, in this case the Powerflex canopy, does affect the amount of light a tree or fruit receives. This can be a disadvantage in growing fruit.

In the end, then, it is important to weigh up and take stock. What is more important, loss of light or no harvest due to heavy rainfall or infestation by the Suzuki fruit fly?