  Starspots are important manifestations of stellar magnetic activity. By
studying their behaviour in young solar analogues, we can unravel the
properties of their magnetic cycles. This gives crucial information of the
underlying dynamo process. Comparisons with the solar cycle enable us to infer
knowledge about how the solar dynamo has evolved during the Sun's lifetime.
Here we study the correlation between photometric brightness variations,
spottedness and mean temperature in V889 Her, a young solar analogue. Our data
covers 18 years of spectroscopic and 25 years of photometric observations. We
use Doppler imaging to derive temperature maps from high-resolution spectra. We
use the Continuous Period Search method to retrieve mean V-magnitudes from
photometric data. Our Doppler imaging maps show a persistent polar spot
structure varying in strength. This structure is centered slightly off the
rotational pole. The mean temperature derived from the maps shows an overall
decreasing trend, as does the photometric mean brightness, until it reaches its
minimum around 2017. The filling factor of cool spots, however, shows only a
weak tendency to anti-correlate with the decreasing mean brightness. We
interpret V889 Her to have entered into a grand maximum in its activity. The
clear relation between the mean temperature of the Doppler imaging surface maps
and the mean magnitude supports the reliability of the Doppler images. The lack
of correlation between the mean magnitude and the spottedness may indicate that
bright features in the Doppler images are real.
