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If you find your plants are not growing well, then it might be time to check your soil pH!
The easiest why to test your soil pH is to use an off the shelf kit, such as Searles Soil pH Test Kit. These kits have everything you require and can be used several times.
Optimum pH range
Soil pH is the measure of soil acidity or alkalinity.
The pH of the soil affects plant growth. If the pH is too acidic (less than 5.5) or alkaline (over 7.5) particular nutrients become increasingly less available to the plant. This can result in plant growth and performance being greatly affected.
Most plants grow well in pH 5.5 – 7.0. Acid loving plants (such as azaleas, camellias, gardenias, Rhododendrons, some Australian native plants, philodendrons, ericas, junipers and spruce) prefer 5.0 – 6.0. Potting mixes and organic mixes perform better at slightly lower pH than soils.
Selecting soil sample for testing
1. Take soil sample from garden bed at 5-10cm deep. For large garden areas, test samples from different areas of the garden.
2. To test potted plants, carefully dig out some potting mix from under mix surface or around root ball.
3. Use Searles Soil pH test kit to test the pH as per directions.
Adjusting pH
To raise the pH of your soil mix in some Garden Lime or Dolomite.
To lower the pH of your soil mix in sulphur powder as per packet directions.
Lastly, lightly rake into soil surface & water in.
Re-test again in 2 – 4 weeks to check results.
