Green
The color green is almost exclusively used in connection with plants in the Bible, and the meaning is closely connected to the meaning of plants as well. Plants, in general, represent facts, knowledge that we can gather from the world. Green plants are ones that are alive and growing. Since life represents love and goodness, it makes sense that green plants are facts that have the potential for good use. It also indicates that they are the kinds of things we learn through directly through our senses, since to identify green plants we need to actually see the greenness.
(References: Apocalypse Explained 507; Apocalypse Revealed 426; Arcana Coelestia 7691)
Arcana Coelestia #2507
2507. 'Of Sarah his wife' means spiritual truth joined to the celestial. This is clear from the meaning of 'Sarah his wife' as intellectual truth joined to Divine Good, or what amounts to the same, spiritual truth joined to the celestial, dealt with in 1468, 1901, 2063, 2065, 2172, 2173, 2198. What the spiritual is, and what the celestial, has been stated quite often already, see 1155, 1577, 1824, 2048, 2088. That is called the celestial which consists in good, that is, which consists in love to the Lord and in charity towards the neighbour; and that is called the spiritual which consists in truth, that is, which consists in faith deriving from love and charity.