Plant Tissue Mineral Content Tests

If a healthy cannabis plant's leaf tips are dried and browned in excess of about 6 or 7 mm or 0.25 inch, there's too much food available, and the plant suffers as a result. If the tips are browned less than a few millimetres or about an eighth of an inch, the plant has sufficient but not harmful levels of food and probably won't get all yellow prematurely. Yellow generally means not enough nitrogen, which is necessary during vegetative growth; gradual yellowing during flowering and at most a pale green just before harvest means the plant probably won't have excess mineral in its tissues at cutting and drying. If one grows within a peat or earthy mix, it's hard to get that pale light lime green colour of dried buds, since breakdown of root zone stuff will provide enough nitrogen for most general flowering growth and the buds will probably remain a dark green. One way of making the plant pale and light green is to move it into a very dark room, or cover it to prevent light from contacting the plant. One keeps the plant in darkness for 2 to 3 days, only then cutting and harvesting the plant. Lack of light will lighten the appearance of pretty well any plant due to chlorophyll breakdown, but of itself won't remove much mineral from plant tissues.

Ever see a picture of a farmer with a stem hanging out of his mouth? There's a reason farmers and horticulturalists do that. If you chew on an average healthy stem, from about midway up the plant, and observe how it tastes, you can get a good general idea of how mineralized its fluids and tissues are. If the taste is somewhat saltish, and the leaf tips are excessively browned, there's too much food. If the taste is more clear and hardly saltish in taste, and the plant is about ready to harvest, the mineral content is good, and one may reasonably expect a decent smoke or vapourization out of it.

Another test is the ash test. With very clean and dry hands, tap about a half inch's worth of ash into a palm, and gently rub it in a circular motion. The darker and grittier the ash, the more mineral content it has. The lighter and smoother the ash, the less mineral the plant has. For personal supplies of medicinal cannabis, the ash should resemble that of a factory made cigarette - with little or no mineral within the plant upon harvest and drying.