Grain Amaranth

How to Grow Amaranth from Seed

Family: Amaranthaceae
Binomial name: Amaranthus tricolour
Life Cycle: Annual

Amaranth can be grown for its leaves or seeds (often callen 'grain'). Some amaranth such as Grain amaranth (Amaranthus hypochondriacus) are different species botanically but are grown in the same way as Amaranthus tricolour. 

When to Sow Amaranth Seeds

Amaranth is a warm season crop. Use the table below to identify the best time of year to sow amaranth seeds in your climate.

Preparation

Amaranth plants are best grown in full sun. Choose a location that will receive at least 6 hours of full sun each day.

Amaranth plants need a well drained soil enriched with plenty of organic matter. Prepare soil by weeding it thoroughly, digging it over to loosen it and adding aged animal manure or compost. Keep the area free of weeds until planting.

Amaranth plants can be grown in containers. If possible choose a variety that’s recommended for container growing. Use a good quality potting mix and make sure your container is large enough for mature plants; a minimum of 20 litres is recommended for amaranth. During the growing season, keep in mind that container grown plants may need additional fertiliser to encourage healthy growth.

How to Sow Amaranth Seeds

Amaranth seeds do not require any treatment (eg soaking, stratification) before sowing.

Amaranth seeds grow best when they are sown directly into the garden.

1. Sow seeds directly in the garden 6mm deep and 60cm apart, with rows 50-80cm apart.
2. Keep soil moist but never wet or dry.
3. Seeds should germinate in around 7-10 days at a soil temperature of 20-25°C.
4. Young seedlings will need protection from pests, pets and weather until they are established.

Amaranth is a tender crop that’s sensitive to frost. Do not transplant seedlings or sow seeds outside until all danger of frost has passed.

How to Grow Amaranth

Amaranth plants may need watering during the growing season. Water when the soil is dry about 5cm below the surface (test this by scratching away a little soil with your finger). Water deeply in the early morning or late afternoon. Avoid watering the leaves of plants to avoid fungal diseases. Learn more about watering here.

If soil was well prepared no extra fertiliser should be necessary. In poor soil or to give your plants an extra boost, application of a high-nitrogen fertiliser or one formulated for leafy greens or herbs can be beneficial:

• Apply slow release fertiliser at the recommended rate when transplanting or when seedlings are 5-10cm tall.
• Apply liquid fertiliser at the recommended rate and frequency during the growing season.

How to Harvest Amaranth

Amaranth should be ready to harvest in approximately 95 days.

Leaves are ready to harvest when they are large enough to eat, and can be harvested as needed. Harvest leaves by pinching off the outer leaves, leaving some on the plant for future growth. Whole stems can also be harvested by cutting them above a leaf node. Eat amaranth leaves as soon as possible after harvesting. Store leaves short term in a perforated plastic bag in the fridge.

Grain amaranth only - Seeds are ready to harvest when they start falling from the tassels. Bend the stems over into a large bucket and cut the seed heads off. Rub the seed heads between your hands to release the seeds. Winnow the seeds to remove the chaff, then place them on trays in a warm spot until they are completely dry. Amaranth seeds can be stored in an airtight container for up to 6 months, or frozen for long term storage.
 

Common Problems when Growing Amaranth

Like all plants, amaranth is susceptible to some pests, diseases and other problems. Below is a list of the most common problems gardeners encounter when growing amaranth plants:

• 

  Aphids are small (2-4mm long) sap-sucking insects that congregate on the new shoots or the undersides of leaves. They can cause leaves to wilt or become discoloured, and also excrete honeydew which can attract ants and other insect pests. To manage aphids, remove them by spraying with a garden hose, apply a soap or alcohol spray, or encourage predatory insects to your garden. Read more about aphids here.
• 

  Frost damage can cause leaves to wilt and go black. Do not plant seedlings in the garden until all danger of frost has passed in spring, and harvest plants before winter. Prune all frost-damaged leaves to avoid them rotting on the plant.