In order to grow high quality, high yielding crops without harming the soil or the environment, and or to be profitable in the long run, a farmer needs to be aware of exactly what fertilizer materials he is putting on his soil and what effects they have – on the crop and on the fragile “soil ecosystem”. Some fertilizers are over priced for what you get, and they may contain materials that can harm crops or the soil. Does it make a difference?
Here are some questions to ask before purchasing any fertilizer:
- Do I need the elements I am buying? (Here is where soil testing comes in)
- Is N-P-K my limiting factors?
- Do I correct soil nutrient excess or just deficiencies?
- How do I decide how much to put on?
- Do I put on what the crop takes off? If so, all 13 known elements or just N-P-K?
- If my soil tests levels are high, do I need anything?
- “Balance the soil- feed the crop”. Do I do both?
- Is this a “numbers game”? If my soil tests 100 kg/ hectare low and I add 100kg, is it corrected?
- What are all the possible ways to increase fertility levels in the soil?
- Are the materials I’m using beneficial to soil life and plant roots?
- The fertilizer may be soluble (go into solution), but is it available to the plant one week after application? One Month? Six months?
The fertilizer “number” game (using potassium as an example)
The total amount of a nutrient in the soil reserve, the amount that is available to the plant, the amount that shows up on a soil test report, the amount in a to of fertilizer and the amount actually used by a plant are all quite different number.
The secret to biological farming is to convert a continuous supply of nutrients from the soil (1); to create plant –available nutrient measured through soil tests (2); to minimize purchased inputs (3); and ultimately achieve a point where the land gets most of its nutritional needs from the soil, therefore requiring only small amounts of supplemental balanced crop fertilizers.
There are different approaches one could use in fertilizing crops. Often, the approach that appears to save money in the short term ends up costing more in the long term. Let’s look at them and the common practices followed:
*Option 1 – use the cheapest fertilizers.
- Apply a minimum of 200 kg/hectare of potassium.
- Apply 100 kg/ hectare of phosphorus.
- Apply three tons of local quarry lime every three to five years.
- Apply 200 kg/hectare of nitrogen for corn
(A soil test might vary recommended amounts applied, but crop removal amounts are still added. The results are the same)
- Easy – can often get goods yields, but may degrade soil. “burn” up humus and cripple soil life.
- Works well on newly farmed soils and with cheap fertilizers, high grain prices and available cheap money (the way it is used to be).
- Profit is not always there
- It takes a lot of cash.
- There is no hope for things to get better in the long run. It is not sustainable.
- It leads to problems:
- Weeds. Pests.
- Trace elements deficiencies.
- Erosion and loss humus; harder soil.
- Stress effects and more dramatic.
- Diseases, both in crops and animals.
- Environmental pollution from excessive fertilizer and chemical use.
- Produces poor quality food.
- Leads to soil imbalance. Things will get worse in time.
- Can lead to higher chemical dependence by reducing biological activity.
**Option 2 – Go to a complete liquid plant food, but do only minimum to build up and balance the soil.
- Get equipment for liquid application.
- Soil and plant tissue testing are a must.
- When and how elements are applied is more critical because fewer units are used.
- Seed-applied at planting.
- Foliar feed in early morning or late day when plants are most receptive.
- The stage of plant growth is also important.
- Less material handling.
- An efficient way to apply trace elements and phosphorus
- Can be very costly; soil-applied nutrients ands much cheaper.
- Still need calcium, potassium, nitrogen and sulphur to be added to the soil.
- Deficiencies can occur over a long period of time because such a small amount of plant food is added.
- Must be applied repeatedly during the growing season, adding to labour and fuel costs.
- Requires special equipment and storage facilities.
***Option 3 – The most logical approach.
- Use a complete soil test as a guide
- Use a blended “natural base” fertilizer that meets your farm’s needs.
- Balance the soil with natural base, high quality fertilizers that are not harmful to roots or soil organisms.
- Supply all needed nutrients, along with plant growth stimulants, in a constant, balanced flow.
- Build the soil with grasses, legumes and manure. Add organic mater, which is food for soil life.
- Get rapid decay or organic matter so nutrients are released for the next crop. Micro organisms eat first – plants get the leftovers and by-products.
- Stimulates soil organisms. They Improve soil structure (aeration, drainage), release soil nutrients and fight diseases and pests.
- Stimulates plant root growth. Larger roots mean less fertilizer is needed for the same yield, and you get better crop quality. There is less stress from environmental conditions. A larger root system can absorb more soil nutrients and water (better drought resistance).
- This option deals with aspects of the soil:
- It works toward improvement. Things will get better with time.
- Less input cost, higher profitability.
- Improved animal health, production and reproduction.
- Requires a better understanding of soil fertility, soil organisms and management practices.