Once the rulers elements are determined in a particular plant, we can know not only their gender and element, also their "personality". I only use this for mixtures(witches likes mixtures, don't know why), is intended to help us to determine compatible plants (only in magic, not in medical uses). To do this, check the table below:
ELEMENT Fire Earth Air Water
Fire * Taurus Gemini Cancer
Earth Aries * Libra Scorpio
Air Leo Virgo * Pisces
Water Sagittarius Capricorn Aquarius *
So, taking the example from the earlier post, pumpkin is water with earth features. To know its personality take water column(ruling element) and earth row(secondary element), remember, ruling element column, secondary element row. We have a female, water with earth features, with moon as ruling planet, Scorpio plant. This is the complete definition of pumpkin in this system.
Compatibility between plants
As happens with people, plants feel sympathy for certain personalities and antipathy for others. Knowing a plant personality we can know compatible personalities. Same for ruling planets.
Back to the pumpkin, if we want use it for magic purposes, a mixture with Cancer plants (because pumpkin is Scorpio) is the best choice. We must be careful not to mix with Taurus or Libra plants. Let's go with ruling planets.
Planets
Compatible:
Venus with all, specially Mars.
Mercury with all, specially Jupiter
Incompatible
Sun-Mars-Saturn
Pumpkin is ruled by moon. As you see, it can be mixed with all of the others planets with no worries. In addition, the Venusian influence makes it perfect for mixing with Mars plants. but never mix a Mars plant with Sun or Saturn plants.
With this I end this short introduction to herbalism which I hope will be useful to someone. Thanks for reading.
Pisces is "mostly" water, cause everything is formed by five elements (Earth, Air, Fire, Water, Spirit) in different degrees, and elements are formed by negative-positive (ying-yang, male-female).
Your question, sorry. Pisces is water (last column) of air(third row). Table looks better in my mind, take pen and paper and copy it properly. If a personality or planet does not appears in list means that the personality or planet is neutral to the other. Two compatible plants works better together than separately, neutral plants works equal together or separately. Most times I only use planets for compatibility.