How do I prevent the leaves of my camellia from rolling up?

Garden Experts
The New Year has not started well for my two camellias. Their leaves are rolling up and dropping off. I have stored both camellias over winter in a well-lit and cool stairwell and water them once per week. Is that too little? I didn't fertilise them during this time. Can I still rescue them?

The GARDENA gardening expert

Dear Ms. K., if the leaves of your camellias are rolling up, this indicates that your plants are not getting enough water, as rolling up the leaf is a mechanism by the plant to prevent evaporation. The camellias must now be kept slightly damp (never wet) using low-lime water at room temperature.
That means: Do not water excessively at any one time, and then leave the plants without water for extended periods. The drying effect can also be incurred through excessive temperature differences between the leaves and roots. If the plant is standing in its pot on a floor which is colder than the ambient temperature, then the roots will provide less water than the leaves evaporate – and the leaves will roll up.
Therefore, please ensure that the “head” and “feet” of the camellia are kept at the same temperature. A very well-lit winter storage location is suitable for camellias, with temperatures from around 0 to 10 °C, maximum 14 °C. A piece of insulation plate or a plant trolley is sufficient to remove the pot from the ground.
You were entirely correct to stop fertilisation. You can start to fertilise again after the flowering period, when the plant comes into bud.