Soil Testing with ARL
The first step in designing a fertiliser programme is to test your soil.
Why soil test?
Soil testing helps you establish the nutrient status i.e. “the reservoir” of your soil. It also means you are able to:
- More accurately assess fertiliser and lime requirements and maximise your fertiliser dollar
- Make better informed management decisions
- Monitor the effectiveness of previous fertiliser applications
- Keep track of fertility trends over time
- Establish a starting point for looking at sustainability and designing fertiliser programmes
Getting the best from your soil sample
The greater the variation in a sample area the more difficult it is to manage and fertilise it correctly. The key to taking a representative sample is to choose sample areas that have a similar soil type, fertiliser history, productivity, topography (slope) and land use. Sample numbers should increase with greater variation in these factors.
You will get the most value from your sample when the area it represents varies the least.
How do I sample for soil analysis?
The greater the variation in a sample area the more difficult it is to manage and fertilise it correctly. The key to taking a representative sample is to choose sample areas that have a similar soil type, fertiliser history, productivity, topography (slope) and land use. Sample numbers should increase with greater variation in these factors.
You will get the most value from your sample when the area it represents varies the least.
Step 1
Select sites to take soil samples from. The samples should be representative of the whole area taken in a transect (line) or grid pattern and should be taken in a way which can be repeated from year to year. Painting fence posts, use of GPS or placing pegs under fences can permanently identify sampling lines. Avoid areas that are not typical of the block/paddock that you are looking to sample from, such as, gateways, troughs, fence lines, unusually high or low fertility “spots” and manure or waste spots.
Step 2
Make sure the core is taken at the appropriate depth. Core depth should be 7.5cm for pastoral soils and 15cm for cropping and horticultural soils. A soil auger can be borrowed or purchased from ARL or your local Ravensdown store. Alternatively a clean spade can be used but it is essential to maintain core width i.e. not sample in a wedge shape and that the core is sampled to the correct depth. Take a minimum of 20 individual cores at 10m intervals.
Step 3
These 20 cores make up one sample and can be placed in one ARL sample bag.
Step 4
Securely close the sample bags and label them clearly.
Step 5
Fill in the soil submission form and put the samples plus the submission form in the pre-paid courier bag and send them to ARL immediately or store in the refrigerator (any delay exposes the sample to excess heat and moisture and can affect the analysis).
Step 6
Standard soil test results will be available 5 working days after they are received at ARL. From there your Ravensdown agri manager or one of the Customer Centre regional agri support agents will be in touch to go over your test results and look at the next steps.
Samples can be sent or dropped off to the lab:
90 Waitangi Road
Awatoto, Napier 4110
Note: Our Sample reception is located in the Ravensdown Compound.
How many soil samples and how often?
We recommend sampling as much of your farm as possible to assist in long-term planning and providing for the overall sustainability of your operation. It’s a small investment to add science to your land management practices.
Maximum advantage from soil testing is best achieved by repeated testing on a regular and planned basis, rather than relying on a “snap shot” in time. For most situations an annual soil test, coupled with plant tissue testing during the growing season is recommended.
You will get the most value from your sample when the area it represents varies the least.
Do I need to do a plant analysis as well as a soil test?
Soil testing cannot tell you if your plants are capturing all the nutrients available, and if the nutrients needed are in the correct proportions. So it’s best practice to soil test in conjunction with plant analysis to give you the most accurate picture of your block and crop. This will enable you to make better informed decisions.
Maximum advantage from soil testing is best achieved by repeated testing on a regular and planned basis, rather than relying on a “snap shot” in time. For most situations an annual soil test, coupled with plant tissue testing during the growing season is recommended.
You will get the most value from your sample when the area it represents varies the least.
Soil Testing Suites
Composite Analysis
Comprehensive suite of tests that provide a holistic assessment of your sample.
Basic Soil Analysis
Price: $68.00
Pasture Soil Analysis
Price: $90.00
Cropping Soil Analysis
Price: $134.00
Extra Analysis
Additional tests that can be added to a composite analysis for more detailed insights.
Mineral N (Deep Nitrogen Test) Analysis
Price: $53.00
Potentially Mineralisable Nitrogen (PMN)
Price: $52.00
Anion Storage Capacity (P Retention)
Price: $27.00
Reserve Potassium (TBK)
Price: $32.00
Anaerobically Mineralisable Nitrogen (AMN)
Price: $25.00
Organic Matter
Price: $27.00
Exchangeable Aluminium
Price: $27.00
Hot Water Soluble Boron
Price: $32.00
Trace Element Testing (EDTA)
Price: $40.00
Resin Phosphorus
Price: $27.00
Total Carbon and Nitrogen
Price: $42.00
EPA Heavy Metals
Price: $112.00
EPA Total Elemental Analysis
Price: Price on Application
Hot Water Extractable Carbon
Price: $27.00
Free Standing Analysis
Individual tests available for specific analysis needs.
