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Plantain is a versatile crop that grows well with other plants. It offers potential high yields of dry matter, around 10-19 tonnes per hectare annually. It needs little water but can tolerate moderate droughts and grows well in warmer soils. It's important to remember that plantain grows better in well-drained, nitrogen-rich soil. When it's time for grazing, cut your plantain to around 25cm before and 5cm after. With proper care, it remains productive for 2-3 years, depending on how well you maintain it. Plantain does have benefits for your cows, for example, it can increase milk production while simultaneously reducing nitrate leaching. A popular time for planting plantain is around May
Plantain is one of the few species that can be managed on a similar rotation length as perennial ryegrass, making it a good fit for the majority of farm mixes.
Plantain produces 10-19 t DM/ha/year. The average yield from spring sowing to May (specialist crop with or without clover) is 11 tonnes/ha. Despite the moderate drought tolerance, plantain still requires moisture to grow well, and under severe drought, yield will be reduced. Under these conditions plants will wilt; however, they recover quickly following rain or the application of irrigation or effluent.
Growth rates of Tonic plantain between spring and autumn range between 25 and 80kg DM/ha/day, potentially peaking at 140kg DM/ha/day in summer. Growth rates during winter are lower (15-35kg DM/ha/day).
Well-managed plantain (0-25% stem) generally has a lower dry matter content than ryegrass pasture and contains less fibre. The metabolisable energy (ME) content is similar. Yet, plantain may be better quality than ryegrass during hot, dry summers. Therefore, milksolids response to plantain appears to depend on the quality of the pasture diet: if pasture quality consistently drops away in summer, then including plantain can increase per cow milksolid production.
Plantain will remain productive for 2-3 years. Plant numbers will decline over this time with the rate of declined depending largely on weed control, nitrogen fertiliser application, and grazing management.
The key management principles for longevity and yield of a special-purpose crop include: managing overgrazing and treading damage, frequent grazing at 25cm height, residual height, and first grazed no earlier than the six-leaf stage.
When plantain is in a pasture mix, the paddock should be managed as a normal grass and clover pasture. This means grazing to residuals of 1500-1600kg DM/ha. When plantain is sown as a special-purpose crop it requires different management.
The key management activities to maximise yield, quality, and persistence can be found in the booklet below, and are outlined in the sections further down the page.
Recommended grazing and seasonal management decisions for plantain.
Download the booklet below
Plantain crops should be first grazed no earlier than the 6-leaf stage (i.e. the plants have six fully grown leaves). This is normally 7-8 weeks after spring sowing. This ensures plants have well-developed root systems to improve survival.
Aim to feed about 20% of the cows’ daily diet (3-4kg DM/cow) in plantain over a sustained period as the rumen requires time to adjust to plantain - like any fed type change. To do this, 5-6ha of plantain should have been planted per 100 cows*.*
Target cover heights are measured by leaf height ignoring the stems.
Pre-grazing height is 25cm (generally this is 4-6 weeks of regrowth)
Post-grazing height should be 5cm
Letting the leaves grow beyond 25cm will not accumulate any more leaf, just increase growth of the lower-quality stem. Dairy cows will readily graze lower than 5cm and management strategies need to be in place to ensure this does not occur. Grazing should be avoided when soils are wet as treading damage has a major impact on plant survival.
|Approximate time to reach 25cm based on data from Waikato*||Time|
These times may change depending on temperature and soil moisture in your region, i.e. slower growth when temperatures are cool or if there is low soil moisture
As a rough guide, a dense (approximately 180 plants/m2) first-year pure plantain crop at DairyNZ had a pre-grazing mass of 3300kg DM/ha at 25cm height.
In comparison, a less dense crop (approximately 80 plants/m2) had a pre-grazing mass of 2300kg DM/ha at 25cm height.
If we assume, on average, that the pre-grazing mass of plantain at 25cm height is 2800kg DM/ha and the post-grazing residual of 5cm will be 1500kg DM/ha, this gives an available grazing of 1300kg DM/ha.
For cows to eat 3-4kg DM per day:
Allocate area based on 20-30m2/cow
Monitor cow grazing - optimum grazing reaches 5cm residual height after about 3 hours
If cows reach 5cm in less than 3 hours, increase allocated area
If after 3 hours the grazing residual is more than 5cm decrease the allocated area
Using the plate meter is another useful way to estimate plantain crops
Like pasture, the rising plate meter can be used to estimate the yield of plantain crops.
Take at least 40-50 readings in a ‘W’ shape across the paddock and calculate yield using the equation: Yield (kg DM/ha) = RPM height (clicks) x 94 + 455. This equation is affected by many factors so it is important to check post-grazing residuals as explained above to ensure adequate herbage allocation. The dry matter percentage of plantain ranges from 9-20% so yields will vary.
Aim to feed 20% of the cows’ daily diet (3-4kg DM/cow) in plantain over a sustained period as the rumen requires time to adjust to plantain.
This requires about 5-6ha of plantain per 100 cows. This is around 0.3 ha per 100 cows each day offered as a 2 to 3-hour break with back-fencing to ensure good regrowth. This system provides for a 21-day grazing rotation, but may need to be adjusted if plantain growth is unusually slow or fast. It provides a daily diet of plantain, which is important as it reduces any rumen adjustment needed if cows are switched from ryegrass to plantain part way through a rotation.
The well-known weed plant plantain was developed into vigorous and upright-growing cultivars. ‘Tonic’ is one of the modern perennial plantain cultivars, it is very different from the common weed types found in pasture, with larger leaves, an erect growth habit and greater winter activity. We specifically refer to ‘Tonic’ because current research is based on sowing this cultivar. There are other plantain cultivars on the market however they may require different management. Talk to your local seed representatives for cultivar options.
Research is in progress but plantain-based pastures may be useful for reducing nitrate leaching while maintaining or increasing milksolids production.
The urine patch is the major source of nitrogen loss to the environment on dairy farms and different forages can be used to reduce nitrate leaching, either by lowering the nitrogen loading in urine patches or increasing the nitrogen uptake from the urine patch.
Research in Canterbury and Waikato the FRNL programme has found that urine-N concentration of cows grazing plantain was 56% lower than those grazing perennial ryegrass/white clover pastures, and 33% lower for cows grazing 50/50 pasture-plantain.
Within FRNL, diverse pastures that include plantain were identified as a promising tool for reducing N leaching. Modelling estimated that, at commercial scale, N leaching could be reduced by 10 and 20% when the area of the farm sown in diverse pastures was 20 and 50%, respectively. This was because of lower total urinary N excretion and lower urinary N concentration (Beukes et al. 2014; Romera et al. 2016).