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28 August 2018 Gary Bosley

Getting it right from day one

You only get one chance to get a crop in the ground at the right time, and that is the first day you do it.

If you have to come back and re-sow, you have lost weeks of productivity and yield. Planning is critical for success. Crop type and time of planting are key, but ask yourself, why do you want to grow a brassica?

In most cases, a brassica crop serves two purposes:

  1. To fill a feed deficit that is left by existing pasture at a particular time of year.
  2. To use as a tool to take out and renew old pasture after the brassica crop has finished.

A brassica crop not only delivers quality feed for livestock, but also allows us to break a pasture rotation by using the opportunity to tidy up perennial weeds that do not need clover safe chemicals.

So a few questions need to be asked:

  • Are the paddocks earmarked for the crop suitable?
  • How did they come through the winter?
  • Are any last minute adjustments needed?

Once you have confirmed the paddock location and have taken a soil test, the next step is to decide what type of brassica you are going to grow: leafy turnip, bulb turnip, rape, raphanobrassica, kale or swede. Then work backwards from the planned grazing date using the number of days that it takes from planting to grazing as per the suppliers’ recommendation.

When you receive your soil test results, if your pH is out, come up with a fertiliser plan and apply lime at the earliest opportunity. Remember, lime can take around six months to correct pH. If possible, plan your spray-out date four weeks before your planting date. This allows plenty of time for old vegetation to die back especially in no-till situations.

There will be less unwanted plants to deal with and it will be easier to create a nice clean seed bed if you plan to cultivate. Whilst it is always tempting to try to get the last graze out of the previous pasture, this can be false economy as you need around 10 cm of actively growing plant leaf to take up the glyphosate effectively. Grazing to the dirt before you spray leads to disappointing results.

Cultivate a firm, flat and fine seedbed to drill into. Remember that brassica seeds are small and do not have much energy inside them. They should be sown with enough good seed soil contact, which supports rapid and even seedling emergence to optimise establishment and achieve canopy closure. Most small seeds should be sown between 10 to 15 mm depth, and always use a slug-bait at sowing in no-till situations.

Spray an appropriate post-plant pre-emergence herbicide, especially if you have difficult weeds or you are sowing a long-term crop such as rape, raphanobrassica, kale or swede. This takes away any seedling competition with weeds emerging at the same time as the crop. Monitor regularly for further weeds and pests and deal with accordingly.

For advice around sowing brassica this spring, contact your local PGG Wrightson Technical Field Representative.

Gary Bosley

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Protect your spring sown crops

01 August 2018

Metarex Inov all-weather slug and snail bait has proven itself to be a critical part of an overall slug management programme to protect a wide range of spring sown crops. 

Slug populations can devastate spring sown crops. Maize and brassica seedlings in particular are extremely vulnerable in their early growth stages. New Zealand trials have consistently shown Metarex to outperform clay coated bait alternatives. 

Metarex is known for its ‘attract and kill’ mode of action, which provides farmers a highly effective bait with excellent longevity characteristics under wet conditions that doesn’t see the bait fall apart in the first shower of rain. It contains the proven active ingredient metaldehyde, in a homogenous blend throughout the bait, which causes irreversible damage to the mucus cells of slugs and snail. The secret to performance is in the unique wet manufacturing process, which results in a durum wheat based bait that is rainfast and highly palatable to slugs and snails. This gives both the ‘attract and kill’ feature as well as its direct contact action. 

Metarex is also Integrated Pest Management (IPM) friendly. The safety to beneficial insects and earthworms allows beneficial insects such as carabid beetles to lend a helping hand for a sustainable integrated pest control programme. The low use rates also provide advantages around storage and ease of handling and application.

Excellent bait ballistics, uniform spreading, high number of bait points and the no dust, no hassle spreading features makes for an effective and user friendly option to combat slug or snail problems.

Contact your local PGG Wrightson Technical Field Representative to find out more.

Supplied byUPL

Get the paddock right

28 August 2018

Time spent now selecting and preparing your brassica crop paddock may pay off later.

Paddock history, location and soil fertility are just three of the considerations that should be kept in mind when deciding where to grow your next brassica crop.

“Be mindful of paddock history with brassicas,” says Murray Lane, Forage Specialist for Ballance Agri-Nutrients. “If previous crops have been infested with wild turnip, it is not recommended to plant swede, turnips or kale into the same paddock. If you have had dry rot or club root don’t plant brassicas, even varieties tolerant to these problems, in that spot for five years following.”

Consider access and suitability for machinery and stock. “Choose a paddock that is less prone to pugging or compaction, and one where you can easily provide grazing stock with drinking water while keeping them away from natural waterways and drainage channels,” advises Murray.

In relation to paddock rotation, think about whether you have pasture that could benefit from a break to address weed and pest issues, contouring, or other performance problems.

“Above all, select your paddocks early,” says Murray. “This gives you time to prepare them properly, which pays off with a better crop. Spray-out weeds this autumn, put in a winter ryegrass, graze that, then spray again before sowing in spring. This will minimise the amount of weeds in the crop.”

Early paddock selection also gives you time to adjust pH and fertility. “Brassicas like a pH between 5.8 and 6.2. Lime applications need up to a year to take full effect so the sooner you select your paddock, test pH and if necessary apply lime, the better.”

Test soil nitrogen, phosphorus, potassium, sulphur, magnesium and boron six months before sowing to inform your fertiliser strategy. “Brassicas can be expensive to grow. Hitting that sweet spot where you get the best yield gains from your inputs, in other words an economically optimal yield, is the aim. Also consider the value of the feed as this influences the size of the gap between the economic and maximum yields,” explains Murray.

Looking further ahead, regardless of base fertiliser needs, the value of placing a starter fertiliser at sowing cannot be underestimated. Cropzeal Boron Boost is a good option for brassicas providing phosphate close to the germinating seed to support early root development, and boron to guard against common problems such as brown heart.

To assist you in planning your next brassica crop, talk to your Ballance Nutrient Specialist or your local PGG Wrightson Technical Field Representative.

Article supplied by Ballance Agri-Nutrients

Spring crop paddock selection

01 September 2018

Soil testing is an important tool in your cropping calendar. It can be utilised to assist in selecting the correct paddocks to use for high value crops, like fodder beet, and for selecting which paddocks can be planted with a lower value crop in order to start the process of increasing soil fertility in areas lined up for pasture renewal.

Soil testing provides the ability to develop a tailored fertiliser programme and focus on the key nutrients required for your farms maintenance programme, or for a specific crop. Fertiliser spend makes up a significant portion of the farm budget, therefore it is always worth taking a measured approach and only applying the nutrients that are needed.

So what are nutrients? They are the 16 mineral elements that plants and animals require to grow and function, with plants getting their nutrients from the soil. Soil testing prior to planning for the season ahead gives a base foundation and understanding for the nutrient levels you are working with. In your farming system, growth or yield will be limited by the nutrient in shortest supply.

Soil testing is an essential component when it comes to nutrient interactions. Having an abundance of one nutrient can effectively antagonise another, or vice versa, where you have a synergy of increased availability of one nutrient due to the increase in level of another nutrient. For example, excess potassium leads to an imbalance of magnesium and calcium, which can have an effect of poor yield or quality, as well as the potential for metabolic disorders in stock to arise.

Another reason behind soil testing is for developing trends across your farm system against previously collected data. It is recommended that you get your PGG Wrightson Technical Field Representative, or Ballance Agri-Nutrients representative to soil test at the same time every year, to maintain consistency. Taking samples six to eight weeks out allows for tests to be sent away, analysed and sent back to develop effective fertiliser programmes.

Sampling depth for soil testing is directly related to the potential rooting depth of the crop. Pasture, or herb paddock samples should be taken at 75 mm, and arable or cropping paddocks sampled at 150 mm in depth.

Fertiliser inputs will be based on your soil test results and will determine if your fertiliser programme is maintenance, or capital. Maintenance nutrient requirements are the quantity of fertiliser nutrients required to maintain a particular soil test level over a one year period. Capital nutrient requirements are the quantity of fertiliser nutrients required to increase the soil test value to the optimum target value, for example increasing soil fertility levels to get an optimal Olsen P for the soil type and farm production level.

Taking a soil test to determine soil nutrient levels, prior to planting crops and applying maintenance fertiliser over the whole farm ensures rates of nutrients applied are in line with dry matter yield goals for your crops and overall farm production goals. Knowing what nutrients are already present in your soil also helps to avoid applying excess fertiliser, thus helping to farm in an environmentally sustainable manner.

For more information on soil testing, contact your local PGG Wrightson Technical Field Representative.

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