The Science Behind Planting
Cotton planting in Australia is well underway in most valleys whilst some early planted cotton in Central Queensland is already well advanced. The question that often gets asked around planting time is: "how precise is precise enough when it comes to planting cotton?" This is not a question that has an easy answer nor can any answer be generalised. A general misconception is that with cotton, being a perennial plant, there is no yield penalty when having an uneven plant stand. However, the fact that cotton has more ability to compensate for planting conditions than corn for example, doesn't mean that seed spacing, depth and seed soil contact are any less important.
If two seeds get planted right next to each other and they both germinate, cotton plants will compete for inputs and therefore not produce the highest yield possible. On the other hand, when a large gap is left when planting, these same inputs will go to waste as there are no plants nearby to utilise the moisture, nutrients or sunlight available. Where the yield penalty in these cases might seem obvious, the less obvious quality issues associated might even be more damaging to a grower's bottom line.
Where most grains are tested at the delivery depot for qualities such size, splits, protein, etc to determine the pricing, cotton prices are based mainly on the fibre length, strength, thickness and colour. Any of these factors, but also the amount of fibre that gets produced, can be influenced by the plant stand in the field due to the availability of factors such as sunlight, nutrition and moisture to the individual plants. For growers that want to improve the quality and quantity of the fibre that they produce it is therefore of high important to determine what the effect of their plant stand is on their overall results. Issues resulting from sub-optimal planting however, can differ per situation.
If you look at an irrigated grower for example that flushes his fields up after planting, correct and even plant spacing might be critical so that the large amount of water available to the plant during the growing season in combination with ample nutrients are utilised effectively. On the other hand, if you look at a dryland grower that grows cotton in a marginal rainfall area, the seeding depth and seed soil contact might be critical as he will only get one chance at planting and has no room for error. In both cases though, even germination and spacing will always enhance the results achieved.
After a number of more marginal growing seasons, as Australia has experienced recently, an often heard reaction when discussing plant stand issues is: "I've got no money to buy a new planter". This is an understandable problem, but as we are now transitioning to what appear to be a couple of years with more water available, it is imperative to make most of the conditions as they present themselves. For example: if you have water security for the next three years, when should equipment that improves the yield be upgraded, now or after these three years?
The key concern, when making these decisions, is to decide whether you even have to buy a new machine or if you are able to upgrade existing equipment for a fraction of the price and reach the same results. With the emergence of companies like Precision Planting that offer aftermarket parts to upgrade mainstream planting machinery, the decision process for updating your planting machinery has changed radically. The one thing that is still the same however is that, when making these decisions, getting advice from the right person can make a big difference.
If you want to discuss your ideas for upgrading your planting machinery, feel free to give me a call; by looking at the results you want to achieve and not being the person that can sell you a planter, I can assist you by giving un-biased advice.
Written by: Reinder Prins. Reinder Prins is the market development manager for Cotton Growers Services and as such is responsible for the Precision Agriculture initiatives within the organisation. Reinder can be contacted on +61 427 - 808 489 or via e-mail on