caldo de cultivo betyder på engelska

breeding-ground▼(figuratively)
noun
[UK: ˈbriːd.ɪŋ ɡraʊnd] [US: ˈbriːd.ɪŋ ˈɡraʊnd]

hotbed [hotbeds]▼(place ideal for the growth of something undesirable)
noun
[UK: ˈhɒt.bed] [US: ˈhɑːt.ˌbed]