Why do we cultivate in protected cultivation?

In the 19th century, our farm began to cultivate fruit commercially. Even then, strawberries were a popular local fruit and were exclusively grown in open fields by us until 2010. However, after our entire strawberry crop fell victim to a severe hailstorm and heavy rain in 2010, we invested in our first sun tunnels at the end of the year. By 2012, we had completely switched to protected cultivation. Over the last few years, numerous expansions have followed, so that today we grow 100% of our strawberries under protected conditions.

The protected cultivation of our strawberries offers a multitude of advantages that enhance both the yield and the quality of the fruit. Growing in sun tunnels protects the strawberry plants and their delicate fruits from adverse weather events such as hail, frost, and heavy rain. This significantly reduces the risk of crop failures and harvest losses, leading to stable production and reliable yields.

Moreover, our strawberry plants are less susceptible to fungal diseases and environmental stress due to the protection of the sun tunnels. With proper ventilation, the plants in the sun tunnels are less prone to fungal diseases due to lower humidity, thus providing preventive protection. This leads to a reduced need for auxiliary and operating materials and allows us to cultivate in a particularly sustainable and environmentally friendly manner.

In addition, protected cultivation meets the increasing quality requirements of trade and consumers. Our strawberries, grown under the sun tunnels, typically exhibit exceptionally high quality, as they have minimal damage or rot and ripen more evenly.

How do we cultivate in protected cultivation?

In August, our strawberries are planted in natural, healthy soil, which is moulded into ridges and covered with a thin black film. This cultivation method warms the soil quickly and promotes soil activity. At the same time, water consumption is significantly reduced as less water can evaporate from the soil and demand-orientated drip irrigation is used in the ridge. In addition, the black film protects our delicious fruit from soiling during the harvest and prevents weeds.

In January, we close our sun tunnels by attaching the greenhouse film to the metal structure and installing the doors. Thanks to the sunlight and the associated warming of the strawberry tunnels, the vegetation starts much earlier.

When the first strawberry blossoms open in March, we deploy numerous colonies of bumblebees for pollination. Bumblebees are particularly important for the cultivation of strawberries in sun tunnels, as here the self-pollination of the flowers is not supported by the wind. The effective pollination of the strawberry flowers by our bumblebees leads to better fruit set and larger, more beautiful fruits.

In each tunnel, we place a colony of bumblebees whose members intensely visit the flowers in search of pollen and nectar. A large amount of pollen sticks to the relatively large, hairy bumblebee body, which is then very effectively carried from flower to flower, resulting in pollination.

Our bumblebees are active from 7 degrees Celsius because they generate the body temperature necessary for flying through the vibration of their thoracic muscles. Moreover, these diligent helpers can orient themselves very well in the tunnel and remain active even in weaker light conditions.

 

Discover our sun-ripened strawberries from Oberkirch starting in spring! Thanks to our natural cultivation in sun tunnels, we harvest delicious strawberries from mid-April in the south of Germany. Due to the warm daytime temperatures and minimal nighttime cooling of the soil, our strawberries ripen naturally and early in the sun tunnels. This protected method of cultivation allows us to offer the highest quality from the region already in the spring, without having to rely on climate-damaging imports.