For lawns, annuals or house plants, take the soil sample from about 2-3" below the surface. For perennials especially shrubs, vegetables and fruit, the sample should be from 4" deep. Avoid touching the soil with your hands.
How To Use Your Soil pH Meter
2. Using the supplied pad, lightly shine 4" 5" (10 12cm) of the probe, carefully avoiding the bullet shaped tip, to remove any oxides that may have formed on the surface of the metal.Wipe the probe clean, using a cotton ball or paper tissue; always wipe away from the tip, towards the probe handle.
3. Push the probe vertically into the moistened soil to a depth of 4" 5". If it does not slip into the ground fairly easily select a new position. Never force the probe.
4. Twist the probe clockwise and counter-clockwise between your fingers several times to ensure that damp soil is well distributed over the surface of the probe.
5. Wait for 60 seconds to acclimatize the probe and note the reading.
6. If the reading is pH7 or higher: Remove the probe from the soil and wipe any soil particles from the surface of the probe. Reshine the probe and insert back into the soil at a different point avoiding the first hole made by the probe.Twist the probe two or three times between the fingers, as before, and wait 30 seconds before taking the final reading.
7. If the reading is below pH7: Remove the probe from the soil and wipe any soil particles from the surface of the probe. Do not reshine the probe. Insert the probe back into the soil at a different point avoiding the first hole made by the probe.Twist the probe two or three times between the fingers, as before, and wait 60 seconds before taking the final reading.
Helpful Tips On Soil Testing
- Don't leave the probe in the soil longer than necessary because the metal electrodes may pit, with the possibility of damage to the meter mechanism.
- Insure that the probe is wiped clean and well dried before storing in order to minimize the oxidation of the metal electrodes.
- Be sure to keep the probe away from metal objects.
- Use the meter only in soil. Do not place the soil testing probe in water.
Troubleshooting Your Soil Tester
- Stones, organic matter touching the electrode.
- Sample area not sufficiently compacted (light soils and potting soils).
- Metal particles adhering to electrode after cleaning.
- Soil not adhered to the probe sufficiently.
- Probe too close to the side and/or the bottom of the pot.
- Soil or potting soil being tested too soon after re-potting.
- A houseplant fertilizer stick or tablet near the probe.
Advice On Working With Soil Types
Sandy Soils - A light, coarse soil comprised of crumbling and alluvial debris . Loam Soils - A medium friable soil, consisting of a blend of coarse (sand) alluvium and fine (clay) particles mixed within fairly broad limits with a little lime and humus.
Clay Soils - A heavy, clinging, impermeable soil, comprised of very fine particles with little lime and humus and tending to be waterlogged in winter and very dry in summer.
ADDING LIME TO INCREASE pH
Lime can be added at any time of year but it does need time to take effect which is why the autumn, winter and early spring are the preferred times. Hydrated lime may take effect in two or three months but ground chalk or limestone may take up to six months. Avoid adding lime at the same time as sulfate of ammonia, superphosphate, basic slag or animal manures. Lime may be used in combination with sulfate of potash or muriate of potash.