From Ishikawa Prefecture and Cultural Heritage Online.
Kenrokuen is a typical daimyo garden of the Edo period, shaped over many years by the lords of the Kaga domain.
It is a stroll garden (kaiyu-shiki). Instead of a garden seen while sitting in a temple or palace room, it uses the whole wide ground: a large pond is dug, hills are built from the earth, and small tea houses are placed here and there, so that visitors can walk around and stop at each one.
There are several ponds joined by winding streams, hills made from the dug-out earth, and many kinds of trees.
The name Kenrokuen means a garden that has all six qualities (roku-sho) named in an old book, the Rakuyo Meien-ki: spaciousness, seclusion, human work, age, water, and wide views.
Matsudaira Sadanobu gave the garden this name. The name board over the Hasuike gate is in his handwriting.
In 1676, the 5th lord, Maeda Tsunanori, built a villa and made a garden around it. This is said to be the start of the garden, often called the Renchitei garden.
In 1822, the 12th lord, Narinaga, built the Takezawa Palace, and the same year the garden was named Kenrokuen.
The 13th lord, Nariyasu, made great changes. He brought water from the Tatsumi Canal, about 8 km away, to make waterfalls, winding streams and a fountain. In 1860 he removed the gate and wall between the two gardens to make one large garden.
In 1874, Kenrokuen was fully opened to the public, and many tea shops opened there.
It was named a Place of Scenic Beauty in 1922, and raised to a Special Place of Scenic Beauty in 1985, the highest rank for a garden.
There is no single right answer. Talking it over with someone at home is a good way to learn.