Growing maize silage on-farm additional benefits

Growing maize silage on-farm gives you the opportunity to renew your pastures.

Modern pasture species1:

  • produce more drymatter.
  • resist pests and diseases better.
  • are more palatable which makes them easier to manage.
  • have a high feed value (ME) so they deliver higher stock growth or production.
  • offer seasonal benefits (e.g. some varieties are better in summer while others are better in winter).

Successful pasture renewal will increase pasture yield by around 3-6 tonnes of drymatter per year1.

Because they produce high yields of drymatter, maize silage crops have high requirements for nutrients especially nitrogen, phosphorus and potassium. This high nutrient requirement coupled with the deep rooting structure of maize, makes it an ideal "sink" for dairy shed effluent.

Maize crops can pull nutrients that have dropped out of the root range of shallow rooted crops such as pasture. Maize silage crops grown in long-term pasture paddocks that have been used for effluent disposal may not require any additional fertiliser resulting in significant cost savings per kgDM of maize silage grown on-farm2.

To determine the nutrient requirements of on-farm maize silage crops soil test and use AmaizeN (available free from

Growing maize silage on-farm gives you two opportunities to eradicate hard-to-kill weeds and grasses such as kikuyu, mercer grass and paspalum.

By selecting the hybrid and planting date you can determine approximately when your maize silage crop will be harvested and ready to feed.

A Waikato trial showed that yields of almost 39 tDM/ha can be achieved from maize silage followed by a winter crop3. This is more than double the annual pasture yield achieved on most New Zealand farms.

Figure 1: Total annual drymatter yields for maize and a range of winter crop options (two-year average data)3

Getting the most out of your run-off?

Many dairy farm run-offs are not farmed to their full potential. In a paper presented at Dairy3 in 2007, Scott Ridsdale (DairyNZ) provided an example which showed that a partially cropped run-off could harvest 86% more drymatter than a traditional run-off4. The partially cropped run-off provides an 83% higher return on assets for the farmer that owns it.

Traditional run-off
30 hectares
Partially cropped run-off
30 hectares
Heifer grazing
75 calves
75 yearlings
Heifer grazing
87 yearlings
Winter grazing
100 cows for 4 weeks
Winter grazing
120 cows for 4 weeks
Standing grass for hay
20 tDM
Maize silage
10 ha or 235 tDM
  Triticale silage
10 ha or 80 tDM
300 tDM or 10 tDM/ha
558 tDM or 18.6 tDM/ha
86% more drymatter from the partially cropped run-off 


1Pasture Renewal Charitable Trust. 2008. The Power of New Pasture.

2Foundation for Arable Research Media Release 2008. Maize silage makes the most of dairy effluent,.

3Densley et al. 2006. Maize silage and winter crop options to maximise drymatter and energy for NZ dairy systems. Proceedings of the NZ Grasslands Association 68:193-197.

4Ridsdale, S. 2007. Are you getting the best out of your run-off. Dairy3 Conference Proceedings.