How to Grow Oat Grass in Australia

Oat grass is the young leaf of oats (Avena sativa, family Poaceae), grown thickly on a tray from hulless grain and juiced raw. It is the mildest of the grain grasses, gently sweet, and usually ready 6 to 10 days from the soak. It grows like wheatgrass and barley grass, but with a far shorter soak.

Three mistakes that matter

1. Soaking oats like wheat. Hulless oats are tender and quick to sprout. One oat supplier soaks them for just 30 to 60 minutes, where wheat soaks for 6 to 12 hours. Grain left too long in water can ferment.
2. Sowing the grain in a heap. Grain piled deep holds water and still air at the bottom, where mould starts. Spread one dense layer, grains touching, and sow a little thinner in humid weather.
3. Leaving water in the catch tray. Roots left sitting in water turn brown and smell. Water from below and pour off what the mix leaves.

When to sprout

Oat grass grows indoors in any month, in a room near 21°C or cooler. Oats are a cool-season cereal whose grain can germinate, slowly, from about 2°C, so a cold bench slows the crop without stopping it.

In a heatwave, grow the tray in the coolest room: warm, humid air favours mould.

Food safety

Bacteria thrive in the warmth and moisture that sprout the grain, and those inside a contaminated seed cannot be rinsed away.

• Use untreated hulless oats sold for sprouting, and soak and rinse them in drinking water only. Grain sold for sowing can be treated with fungicide, as which seeds to sprout explains.
• Wash your hands before handling grain or grass. Wash and rinse the trays, jar and tools, then sanitise them before the first batch and between batches. Use a dishwasher that can sanitise, usually on its longest, hottest setting. Otherwise, soak them in very hot water (77°C for 30 seconds). Or soak them for 30 seconds in plain unscented household bleach at 25 mL to 10 L of cold water. Make the bleach up fresh each day and use it as its label directs. Let them air-dry.
• Drink juice as soon as it is made. Wash the scissors and juicer after every use.
• Potting mix can carry Legionella bacteria. As the bag warns, wet it down, wear gloves and a P2 mask, and wash your hands afterwards.
• Keep trays, grass and juicing gear away from raw meat, poultry and seafood. Store cut grass above them, in a fridge at 5°C or colder. Serve anything cooked for someone at higher risk straight away. Otherwise cool it, keep it in the fridge, use it within a day of cooking and reheat it until steaming hot.
• Mould on the grain, slimy brown roots or a sour smell end a tray: compost the grain and mix. Grass can carry harmful bacteria while looking, smelling and tasting normal, so none of those is a test of safety. Sprout problems and safety covers more signs.

What you need

Use a shallow tray with drainage holes inside a solid catch tray. An upturned tray with a few holes or slits makes the cover. Fill the tray with 1 to 2 cm of seed raising mix, or lay a coir mat. Add clean scissors, a spray bottle, a juicer made for grass and hulless oat grain.

For any other tray, cover its empty base with dry grain in one even, dense layer: that is the amount to soak. For the first rinses, use a sprouting jar, a jar with a mesh lid or a colander.

Soaking and Sowing

A short soak and a day of rinsing put the grain on the tray already showing a root tip.

1. Rinse the grain in cool water and lift out chaff, stones and broken grains.
2. Cover it with two to three times its volume of cool drinking water. Soak it for 30 to 60 minutes. Other suppliers give longer soaks, of 4 to 12 hours.
3. Drain, rinse and drain again, and never soak it a second time. Rest the jar mouth down, or the colander over a bowl.
4. Rinse and drain every 8 to 12 hours until most grains show a tiny white root, often after one or two rinses.
5. Wet the mix through and let it drain. Spread the grain one layer deep and press it lightly on, unburied.
6. Put the cover on and keep the tray dim until the shoots stand 2.5 to 5 cm tall.

Under the cover, mist the grain once or twice a day until the roots bury themselves. In a hot, humid kitchen, lift the cover once the roots grip, since grain covered too long can go mouldy. Due to quarantine restrictions and our shipping policy, we cannot send oat grass seeds to Tasmania.

Day by day

Success on the tray comes down to damp roots, dry blades and moving air. Days count from the start of the soak.

To water from below, fill the catch tray, let the mix soak for about ten minutes, then pour away the rest. In humid weather, keep a fan on low or a window open nearby.

Cutting and Storing

Oat grass is ready at about 10 to 15 cm, while the blades still stand upright. Cut what you need with clean scissors, 2 to 3 cm above the mix; the rest keeps growing.

Coeliac Australia's diet guide says wheat grass and barley grass contain no gluten, but lists oats as a gluten source in some people. With oat grass, the worry is the grain and husk near the cut, which a high cut leaves behind. Anyone with coeliac disease should talk with their medical team before eating oats, as Coeliac Australia advises. It says only oats specially produced free of wheat, rye and barley contamination may be suitable.

To store a cut, stop wetting the blades 8 to 12 hours beforehand so they are dry to the touch. Seal them in a clean bag or container in the fridge. They keep for up to about a week. Rinse under cool running water just before use, and compost the roots and mix after the last cut.

Hulless oats also sprout in a jar. Soak and rinse them as Soaking and Sowing describes; short roots show 1 to 3 days from the soak. Sprout only what you need, since grain sprouts keep growing in the fridge, and cook them as Food safety describes.

Common problems

White fuzz on the roots. Root hairs are fine, even and white, grow only on the roots, and flatten when misted. Mould can be white too, but it spreads in cobwebby patches over grain and mix, stays when wet and smells musty. End a mouldy tray; never cut above it.

Sour smell or slimy, brown roots. End the tray as Food safety describes; Three mistakes that matter gives the fixes.

Grain that will not sprout. Rolled oats will not grow, and hulled oat groats often fail, because hulling can damage the tender grain. So does old grain, or grain left to dry after sowing. With no roots or shoots after a week, compost it and start again.

Tips

1. For a steady supply, start a small tray every two or three days.
2. Store dry grain sealed in a cool, dark, dry place.
3. The grain grasses article compares oat, wheat and barley grass.