How long will it take to see the effect of geomantic omen in Yin House after burial?

Grandchildren get quick results, some get quick results, and some wait for the right time (such as during the year). The son's effect is slow but not obvious. If they take effect, they will only have a slight impact. Otherwise, there has been a saying that ancestral graves are green since ancient times. Why have they never heard that Father Graves is green? This is a fact.