With dairy farmers currently planning summer crops for their herds, regular maize growers will be thinking hard about whether it suits this season with lower milk prices.
FutureDairy’s Professor Yani Garci said management had a big impact on the profitability of a high input crop such as maize.
“A profitable maize crop is achieved by optimising both yield and nutritive value. Very high yielding maize crops are not necessarily the most profitable as they tend to be higher in fibre and therefore have lower nutritional value.”
Professor Garcia has five tips for achieving a profitable maize crop this season.
Tip 1: Do not apply the full amount of nitrogen fertiliser unless you can ensure water will not be limiting. If water is likely to be limiting, adjust nitrogen application. For example, N application both presowing and at V6 stage are highly recommended, but if you need to adjust, save the N for the V6 stage.
Tip 2: Time water application for greatest response. If irrigation water is likely to be limiting, resist the temptation to under-irrigate throughout the whole season. You’ll get a much better response to water by timing water applications to the critical periods at crop establishment (up to about six leaf stage) and the five to six week period around tasselling.
Tip 3: Match fertiliser rates to target yield. Aim to apply at least 80% of nutrient requirements as fertiliser. Soil testing or tissue sampling is the best way to determine fertiliser rates. However, as a rule of thumb, high yielding maize crops remove 10-12kg N/t DM/ha, 2-3kg P/t DM/ha and 8-10kg K/t DM/ha grown
Tip 4: Time nitrogen applications for greatest response. Ideally apply in four stages (if fertigation method is available): pre-planting, planting, at 45cm high (V6) and at tassel emergence (V12). If this is not possible, split nitrogen application into about half pre-sowing and about half at V6. If a limited amount of nitrogen is available (eg less than 120k N/ha) it is better to save it for around the V6 stage.
Tip 5: Adjust plant density to nutrient and water availability. Sow for a plant density of about 80-85,000 plants/ha if irrigation and fertigation (or pre and post sowing application of N) are available. With full irrigation and fertilisation regimes we have found that higher plant density (100,000) results in higher yield but overall silage quality drops due to excess fibre content.