Log in



How to do a soil test

  • soilFertiliser is the most expensive input on most farms – so you can’t afford to make mistakes or get ripped off through ignorance.
  • Go to the appropriate place to get the soil test kit.  Soil testing labs, fertiliser companies or stock and station produce stores have them and so do some vet clinics.
  • In the kit will be a set of plastic bags and instructions.  They will also give you a returnable soil auger.
  • Select the paddocks you want.  You may only want to do a few each year.
  • Then select “sampling lines” in there paddocks to keep to the same area each time you sample.  Do this by marking fence battens to show your sampling line to walk along each time.
  • If it’s all the same soil type one sample bag will do.
  • If there are different soils in the same paddock or different slopes, sample them separately.
  • If parts of the paddock have been managed differently, then treat them as different samples.
  • Take 15 or more cores, 75mm deep per soil type, and put in the bag.
  • Give each bag a number and record where they came from on the farm.
  • Get the samples to the lab straight away.
  • When sampling, keep away from gateways, stock camps (popular spots for stock to rest), around troughs, gateways, around trees and away from hedges.
  • Make sure dung from your boots doesn’t contaminate the top of the core when you press the corer into the ground.
  • Sample in the same month each year, usually a few weeks before you apply the fertiliser.
  • You need only soil sample every 2-3 years.
  • Remember that a soil test is just that – a soil test.  It will not tell you how much fertiliser to apply.  To do this you will have to show the soil test to a fertiliser consultant who will work out how much to apply to fix any nutrient deficiencies.
  • Good soil test reports show you the normal level for each component then the range.  It will then plot this as a bar graph to make it easier for you to see if you are above or below the normal levels.
  • Remember there is no benefit from putting on more fertiliser than you need to redress the balance.
  • Be wary of being totally bamboozled by too much information from complex test reports that you don’t understand.
  • If you’re not sure what you’re doing, seek simple advice to make sure your are getting value for money.


Related items

Go to top

Sign up for my monthly newsletter!

Get all the latest news along with practical tips and expert advice.