Bees need clean water, nectar but above all a rich and diverse pollen.
In addition to a good diet, beekeepers can keep their hives healthy by having a young queen and regularly changing its frames.

As for all living beings, healthy food equals healthy bees.

The queen is the cornerstone of the hive. The queen must be young and healthy. Usually, a queen lives 3 to 5 years, depending on the number of eggs laid per year. To know the age of the queen, there is an international color code. For example, 2018 is the color red.

It is also essential to change the frames. Because bees raise their larvae in the frame’s cells, they get dirty, smaller and the wax becomes black.
You have to rotate the frames every spring. Meaning to remove 3 to 4 old black frames, and replace them with new ones.