Moisture/Light Meter

The rapitest® Light and Moisture Meter is an invaluable tool for the homeowner. The meter is supplied ready for use. It does not require batteries. There are two meter scales displayed on the dial. The top scale is numbered from 1 (Dry) to 10 (Wet). This is the moisture reading scale. The bottom scale is lettered from A (Low) to H (High). This is the light reading scale, indicating the minimum amount of light the plant should receive.

How To Test For Light

1. Push the selector switch to “light”.
2. Hold the meter so the narrow, purple, rectangular “window” on the top of the meter case is in the same position as the surface of the leaves at the top of the plant. Do not obstruct the window from the light.Make sure there is no shadow cast by any part of your body or by leaves of the plant.
3. Hold the window toward the plant’s light source and take a reading from the lettered scale. (The light is converted to electrical energy, which moves the meter needle.) Note your meter reading. Interpreting Your Readings

1. The letters from A to H indicate an increasing amount and quality of light. No plant in a position that registers an “A” reading will likely do well, while “H” may be too bright for some plants. In the table provided, plants are listed alphabetically by their popular names. Check the name of the plant being tested, and look at the guide letter listed in the column headed LIGHT .This is the plant’s minimum light requirement. If your reading was lower than this letter the plant should be moved to a better light location.

2. EXAMPLE:You are checking a Dumb Cane (Dieffenbachia).The guide reads E. If your light reading is E,F,G or H, the light is equal to or greater than its minimum requirements. If your light reading is lower than E the plant is not receiving enough light. If you are growing under artificial light, you need to move the plant closer to the light source, or intensify the light source. If the plant is growing by natural light, you need to change the plant’s location or give it some supplementary artificial light.

How To Test For Moisture

1. Insert the probe, vertically if possible, into the pot half way between the edge of the container and the plant stem. In potted plants, the depth of penetration will be influenced by the size of the container. Probe deeper in a large pot, shallower in a smaller one. A good rule of thumb is to probe about 1/2 to 2/3 of the way down from the surface. For very large containers (over 12" in diameter) place the probe closer to the stem (about 1/3 of the way from the stem to the edge of the pot.)
2. While pushing the probe into the soil you may note that the meter reading varies as the probe moves downward.This is because the moisture conditions are not uniform. Certain types of soil have a tendency to create moisture pockets, which might give you a false high reading in one small area of the soil.We recommend you take at least two readings in order to confirm your findings. (Note: probing aerates the soil, which is good for the plant.)
3. Note your meter reading.
4. Remove the probe from the soil by pulling the probe handle, not the wire.Tugging the wire may, in time, result in a malfunction.
5. Wipe the probe completely clean with a soft cloth or tissue before taking another reading or when finished.

Important: The meter is designed and constructed for test readings. The probe should not be left in contact with moisture for extended periods of time.