Perennial Ryegrass is the most commonly used feed for dairy cows across the world!

It’s easy to establish and is great at fattening up your cows. It also has a long growing season, recovers rapidly after grazing and can effortlessly regenerate after a dry spell.

The average production of perennial ryegrass on commercial dairy farms in Australia is about 10 tons of DM/ ha/ year. But, it's quite possible to get more than 14 tons of DM/ ha/ year, with better irrigation, fertilising and grazing management practices.

Let's talk about how to sow, establish a thriving perennial ryegrass pasture!

How does perennial ryegrass look?

The plant is densely tufted and has a fibrous root system. The stems usually measure around 30 to 90 cm in length. The dark green, hairless leaves of perennial ryegrass are about 7 mm in length. The leaves also have a shiny under surface.

Lolium perenne - commonly known perennial ryegrass have fine hairless dark green leaves that measure about 7 mm.

Lolium perenne - commonly known perennial ryegrass have fine hairless dark green leaves that measure about 7 mm. Source: Wikimedia

Perennial Ryegrass Seeds:

Perennial ryegrass seeds are flat, awnless and are about 6 mm long.

Perennial ryegrass is usually sown in early autumn. But it can also be sown in spring if you maintain a clean seedbed and can irrigate the seedlings adequately.

It can either be sown into a prepared seedbed or directly drilled into the paddocks. To get good germination, do not drill the seeds more than 10mm in depth. Also, ensure that the paddocks are relatively weed free, before drilling ryegrass seeds.

The actual seeding rates will depend on your location, soil profile and average annual rainfall.

For example, within Australia, regions that are to the North of Sydney typically use a seeding rate of 20 kg ryegrass along with 4 kg of white clover per hectare. While regions to the South of Sydney use about 15 kgs of ryegrass along with 5 kgs of white clover per hectare.

So it's best to adopt your local seeding rates.

Choosing the right ryegrass species:

Again, the right ryegrass species for your farm will depend on your soil type, fertility, rainfall and growing season length. Because choosing the right species is a key step in establishing a successful, persistent and thriving ryegrass pasture - it's best to ask your local farm advisor about the right species for you.

With that out of the way, let's briefly talk about companion species that can be sown alongside perennial ryegrass. Phalaris, cocksfoot and tall fescue are commonly sown along with ryegrass. But the most popular companion plant sown along with ryegrass is clover. Sowing a clover species along with perennial ryegrass offers two key advantages.

  1. Clover fixes and makes more Nitrogen available to your ryegrass pasture.
  2. Clover also improves the overall nutritive value and palatability of the ryegrass pasture.

However, in low rainfall areas, phalaris and cocksfoot are more suitable. Cocksfoot has a lower winter production value than phalaris but it tends to grow better in soils that are shallow with low fertility and high acid levels.

Varieties of phalaris differ in their level of winter production and acid soil tolerance. Older semi-winter dormant varieties like Australian phalaris showcase a good winter production and good persistence in conditions with low fertility and set stocking.

Perennial ryegrass has good autumn and winter production. It grows well in areas with a rainfall of above 700 mm. However, there can be huge differences in autumn and winter production between old and new varieties of perennial ryegrass.

More recently, varieties like Holdfast and Landmaster claim to have better winter production but they have to be grazed rotationally for good persistence. Similarly, recent winter-active tall fescue varieties have been known to exhibit good persistence, palatability and early autumn production.

Assessing soil fertility levels:

Before establishing a new ryegrass pasture, you need to prepare your paddocks.

Take a soil test much before the sowing date to allow time for correcting soil fertility problems. Phosphorous, potassium, sulphur, soil pH, aluminium, sodium and electrical conductivity (ECe) levels need to be examined and addressed before sowing.

It is recommended to apply phosphorous at sowing, even if the soil is highly fertile. This will maximise germination and ensure rapid growth.

Take a soil test before deciding on your fertiliser plan.

Take a soil test to assess your soil fertility level before deciding on a fertiliser plan.

Potassium and nitrogen fertilisers in the form of urea or diammonium phosphate should not be applied at the time of sowing. Because they can damage the seed and reduce germination.

Clover germination can be affected by deficiencies in potassium and this should be corrected one year before sowing. Nitrogen can be applied as urea after germination, or even as monoammonium phosphate before sowing to help increase the growth and vigour of the plants.

Soil pH and aluminium levels are very important to consider when sowing phalaris and lucerne pastures. Both phalaris and lucerne are extremely sensitive to high levels of aluminium that happen due to acidity in the soil.

Aluminium levels above 8 mg/kg CaCl2 in the topsoil within the top 10 cm can be corrected by applying lime.

Aluminium levels above 5 mg/kg/CaCl2 in the subsoil are not conducive to the growth of phalaris and lucerne and thus should not be sown in such conditions. Instead, cocksfoot can be used as an alternative.

The right fertiliser application rates must be recommended by a professional after scrutinising the results of the soil test.

What to do after sowing?

  • After the pasture has germinated, try to pull the grass without roots coming out. If you’re able to pull off the grass neatly, you’re free to set your cows on the pasture.
  • Monitor and control both weeds and pests as they’re spotted.
  • A short grazing period in early spring will boost tillering.
  • Phalaris (if grown) should be allowed to run to head in its first year to give allowance for root development and help boost persistence.

Closing thoughts:

Having invested your time, effort and money into establishing ryegrass pastures, you'll want to maximise your yields. Practicing sound rotational grazing along with maintaining irrigation and fert records can go a long way in helping you achieve maximum yields.

Consider using our free forever tool to maintain all your grazing, irrigation and fert records.

We also offer automatic pasture measurements to help you take effective daily grazing decisions. Plans start at $8 per ha per year along with an annual fee of $1099.

And lastly, if you've read so far, there's a good chance that you'll be interested in our free guide on growing profitable ryegrass pastures.

- The Dedicated Team of, 2021-02-22