Sunlight during day time & Moonlight during night time, through it's rays, is the primary source cosmic energy on Earth. However, cosmic energy is emitted by all the cosmic objects, whatever farthest or nearest position from the Earth. These energies are in the form of gravitational forces working between Earth & the respective cosmic object and other forms of eneries which are emitted and/or reflected on to the earth's surface.
Moonlight is received on Earth at its fullest intensity during fullmoon nights, whereas it is zero during newmoon nights.
All such energy forms have influence on specific plant pert and/or entire plant; for example, Moon's influence is on radial growth of root & shoot from the center (germinated seed). Moon's gravitational force also influence sap movement in the plant; upward movement of sap during waxing phase & downward movement during waning phase.
Similarly, influence of inner planets is on vegetative growth i.e. Sun inluences growth of vegetative parts such as stem & branches, Mercury & Venus influence phylotaxy (leaf formation, shape & arrangement) whereas outer planets (those planets which are orbiting outside Earth's orbit) have influence on reproductive parts like Mars on flowering, pollination & ovule fertilization, Jupiter on fruit formation, maturity & ripening and Saturn influence on seed formation, maturity & vigor.
The 9 planets (navagrah), 12 Zodiac signs & 27 Constellations have been categoriesed into four groups Viz. Fire, Earth, Light/Air & Water, based on their affinity to respective elements. These celestial bodies have influence on growth of various plant parts as per their element viz. Fire for Fruits & Seeds, Earth for Roots, Air/Light for Flowers & Water for Leaves.