Brihat Samhita
पक्षैश्चतुर्भिरनिलस्त्रिभिरग्निर्देवराट्च सप्ताहात् । सद्यः फलति च वरुणो येषु न कालो अद्भुतेषुउक्तः ॥ ३२-३० ॥
The effects of the Anila (Vayu/Air) Mandala manifest in four fortnights (two months); those of Agni (Fire) in three fortnights (one and a half months); and those of Devarat (Indra/Earth) within seven days. The Varuna (Water) Mandala bears fruit immediately (Sadyah). These timings apply to all wonders/portents where a specific time has not been otherwise stated.
english translation
pakSaizcaturbhiranilastribhiragnirdevarATca saptAhAt । sadyaH phalati ca varuNo yeSu na kAlo adbhuteSuuktaH ॥ 32-30 ॥
hk transliteration by Sanscript