First indirect mentioning of Volčji Potok is dated to 7^th April 1220 when in some gift document, issued on Turjak, dominus Hermannvs de Wolfsprach is mentioned. The name Wolfsbach is encountered in Volčje na Blokah near Stari trg pri Ložu and mentioned Herman could be descending from there.
In 1380 in some document a court is mentioned - ze Wolfsbach vnder dem hoff but there is no mentioning of a castle. It is possible that in the middle ages only the court existed which was a center of a smaller estate which can also be concluded from a totally non-castellan name of supposed castle building which was located nearby later manor. Owners of a new manor are from the 16^th century on mentioned many times. According to Valvasor in 1595 the owner of the estate was Nikolaj Bonhomo and his heirs in the beginning of 17^th century abandoned the castle building, which had nothing to do with the ruins on the top of the hill.

Valvasor's veduta from 17^th century, the only known depiction, shows encampment as two-storeyed, built on rectangular ground plan, with already uncovered square turrets and a strong roundel in the background. Architectural characteristics (arrow-loops, shooting-loops) of the ruins dates its origin to the era of mature Renaissance when all over the land fortifications were built due to Turkish danger. The origin of "trouser"-like shooting-loop cannot be imagined before 1500.
It seems that the supposed mediaeval castle was really an independent Renaissance fortification which held its function for a few decades or maybe a century and then it stopped existing. We can affirm that the fortification was actually nothing more than anti-Turkish refuge and this statement is also supported by Valvasor who also lists it at one of the encampments of the time. So the location for the testified mediaeval court should be searched for elsewhere, most likely on the same place where later a new manor, destroyed in World War II, was constructed. It was located at the foothills where nowadays two large artificial peacocks are located. Until today only thing preserved and renewed are garden pavilion, castle chapel and a staircase which leads to a former castle park on the area where arboretum is located nowadays.
To see the ruins located on the western slope of the hill inside arboretum you will have to, like all other visitors who want to see the flowers, pay the entrance fee (local residents probably know of some alternative side path).