What is soil preparation?
Soil preparation methods have been used for many years to create a firm, weed-free seedbed for the rapid planting & germination of seeds.
While it may be one of the more time-consuming tasks on the agricultural calendar, its also the most effective, cost-efficient method for creating a healthy growing environment.
For those in the agriculture sector looking to maximise the health, yield, and quality of crop production for the season(s) ahead, the equation is simple: happy, healthy soil results in happy, healthy crops.
Without soil preparation? Crops are unlikely to achieve the kinds of results the market demands.
1. Test your soil regularly
Not all soils are created equal. What works for one field may not, necessarily, work for another. The time, energy, and fuel required to effectively prepare the soil for planting depends on the specific issues identified above or below the surface.
Regular soil testing is a must for identifying these problems. Self-test kits are usually targeted at domestic users rather than commercial agricultural crop-growers, so it’s best to consult with your local New Zealand soil service provider to get the process underway.
The testing process provides valuable insights into your soil’s pH, Phosphorus, Potassium, and Soluble Salt levels. For example, pH is a measure of the soil’s acidity level which, when experiencing change, can affect the growth of plants and crops alike. In most cases, soil with a pH level above 7 is considered Alkaline, while below 7 is Acidic. The aim of managing your soil’s pH isn’t to achieve a given level – Acidic or Alkaline – but, rather, to maximise the availability of nutrients to the plants that call it home.
With this kind of information at hand, soil experts such as Leicesters are able to make informed decisions and uniquely tailor the preparation process to bring the soil up to standard.
When executed successfully, soil testing saves time and money in both the short and long-term. It cuts out unnecessary treatments early on, while saving crops that would have otherwise been doomed to low yields or outright failure over time.
What about soil pests?
It’s worth noting that standard soil tests do not turn up information on insects, diseases, or chemical residues which may or may not be present within the soil.
This shouldn’t be seen as an invitation to ignore these issues. Far from it, in fact. Soil pests and pathogens are a ticking time bomb residing in your soil. Rhizoctonia Solani and Pink Rot are just two examples of these harmful diseases, and the kinds of long-lasting impact they can have on your soil and the tomato, apple, strawberry, carrot, onion, and other vegetable crops grown within it.
Soil fumigation and disinfestation remains the go-to method for addressing these issues. To maximise the effectiveness of these treatments, preparations should be underway during the testing phase. Soils that are found to be too wet – or too dry – for example, reduce the effectiveness of the fumigation process (a simple squeeze test should suffice). Soil temperature should also be monitored: temps between 10-29c measured as a depth of 15-20cm make for ideal conditions.
2. Cultivate, plow, and till
The plowing, tilling, and cultivation of land remains a core pillar of successful crop growing. It’s also one of the most important steps in the soil preparation process. The act of turning and loosening the soil maximises yields and enhances microorganism activity, while also breaking the system of capillaries beneath the surface and preventing weed growth.
This process also:
- Cuts, crushes, and mixes the soil.
- Incorporates organic material and leftover residue from previous crops.
- Prevents the loss of moisture from evaporation during the summer months
- Destroys weeds that have already emerged which are competing for nutrients, water, and sunlight.
- Loosens the soil, supporting the growth of earthworms and microbes, and allows the roots of new crops to penetrate deeply into the soil and breathe easily.
Does cultivation affect the fumigation process?
Cultivation is crucial where soil fumigation or disinfestation is planned. Clearing the soil of fresh or decaying plant material, pulverising clods, and removing plant trash from the surface ensures soil fumigants can be absorbed and diffused effectively. The deeper the cultivation, the better the penetration of the fumigant. A depth of at least 30-35cm is ideal.
Soil fertilisation is an effective way to improve the microbiological activity within the soil.
Farmers are encouraged to apply manure every 3-5 years to enhance soil properties, along with mineral fertilisers during soil tillage.
Fetrilising best practices suggest that mineral fertilisers first be applied before the sowing process begins, as well as during crop maintenance after they have emerged.
Liming should also be considered in cases where soil analysis shows a lack of calcium ions i.e. the soil is too acidic.
4. Fumigate & disinfest
Whether you’re planting root vegetables, berries, or fruit trees, fumigation and disinfestation remains a vital component of the soil preparation process. Among other benefits, it keeps soil pests and pathogens at bay, and cultivates a healthy, sustainable, and profitable environment for crops.
In doing so, soil fumigation products are able to:
- Improves plant aesthetic, which is vital for crops destined for store shelves.
- Improves plant health and, as a result, crop yields.
- Increases profits, cutting down on money lost salvaging or re-planting affected crops.
5. Address remaining soil concerns
The steps outlined above take a birds-eye view of the soil preparation process, but the specifics of each treatment depends on the make up of your soil, your region, and the results of any soil tests. Some of the specific issues commonly addressed during this process include:
- Do you have clay soil? Coarse sand, compost, and peat moss are all effective treatments.
- Do you have sandy soil? Aged manure, peat moss, or sawdust with added nitrogen can do the trick.
- Do you have silt soil? Consider adding gravel, compost, or coarse sand.