Organic growth comes from a company's existing business, as opposed to growth powered by acquisitions.
It's important to know whether growth is organic -- an increase management was able to get from its existing business -- or the result of something like a one-time acquisition.
Organic chemicals are compounds composed of chemically combined carbon. That includes most animal and vegetable products as well a most plastics and many synthetic chemicals. The rest are inorganic chemicals, i.e., those not composed of carbon, which usually means materials of mineral origins (other than oil, coal, or natural gas).
Organic gardening refers to produce raised without the use of pesticides and sometimes chemical fertilizers.