In astrology, the Earth signs are concerned with production or output, whereas the Water signs are concerned with consumption or input. The fire and air signs are neither consumptive nor productive -they just ARE.
Taurus always thinks in terms of PROFIT or GAIN. Capricorn is concerned with USEFULNESS and ECONOMY. Virgo needs to IMPROVE or OPTIMIZE. Cancer, on the other hand, thinks in terms of what it NEEDS or is DEPENDANT on. Scorpio is DESIRE or the need to POSSESS, and Pisces is DRAIN, ABSORPTION, or LOSS.
In summary, the Earth signs represent productivity, constructivity, or gain, while the Water signs represent consumptivity, destructivity, or loss. The predominance of Earth or Water in your chart will determine whether you are more of one or the other. Count the number of planets in Earth or Water signs in your chart. If the time of birth is unknown, and you do not know the Ascendant and/or Midheaven use only the ten known planets.
Two or three planets in Earth signs is normal, and should ideally be balanced with two or three planets in water signs. This means that you produce and consume in equal amounts and are neither wealthy nor in debt.
When there are more than three planets in Earth you are very productive, but if there is an equal or greater number of Water planets, it all gets wasted or negated. People with too many water planets and not enough earth planets are always in debt or at a loss in some way.
I know someone with three planets in Earth and four in Water -plus the Ascendant (making 5), and no matter how hard he tries, he always eventually lands in the gutter. He also has a shortage of fire signs (only the Midheaven) which doesn't help any (lack of energy, motivation). He does however excel in talking and socializing (grand air trine).
WHICH planets in earth or water, can fine - tune the interpretation. Someone can have an equal amount of Earth or Water planets, but are they well placed? That is, are the planets and the signs their in compatible?
Moon or Venus in Taurus, for example, are much better or more productive than Sun or Mars in Taurus. This is because the Moon and Venus are feminine planets and more at home in the feminine sign of Taurus. Sun and Mars, on the other hand, are masculine planets, and not really compatible or well placed in Taurus which is a feminine sign.
Both groups will produce, but the quality will be superior for the former, where the gender of both the planet and the sign match. Likewise, there will be GOOD and BAD water sign placements.
In general, Moon, Venus, Saturn, Neptune, Pluto, and Midheaven do better in Earth or Water signs, than Sun, Mercury, Mars, Jupiter, Uranus, or Ascendant.