Globe amaranth

Globe amaranth: how do you recognise it?

Habit

Upright, branching annual, 30–40 cm tall and about 30 cm across.

Leaves

Narrowly oval to oblong, 5–10 cm, opposite, green to grey-green and softly hairy.

Flower

Round heads of 2–3 cm on long stems, made of papery bracts with tiny flowers tucked between them, from July to October.

Colour

Purple, magenta, pink, lilac, white and red; the colour hardly fades when dried.

Seed

Small, woolly seed in the faded heads; it germinates better after soaking overnight.

Flowering: July–October · Sowing: March–April · Plants: May–June

Why grow it?

• Flowers tirelessly from July until the first frost, with little effort.
• One of the best flowers for drying: the heads keep their shape and colour for a long time.
• A sturdy cut flower that lasts well in a vase.
• Brings bees and butterflies to the border, the cutting garden or the patio.
• Copes with heat and drought better than most summer annuals: ideal for a dry, sunny spot or a pot.
• The dwarf varieties suit edging, window boxes and containers.

Globe amaranth: where does it grow best?

• Full sun and warmth: the sunnier and warmer the spot, the more it flowers.
• Well-drained sandy or loamy soil, acid to chalky; heavy, wet clay does not suit it.
• Dry to moderately moist: once rooted it tolerates drought well.
• Plant 25–30 cm apart; a 40 cm pot holds three to five plants.

Light

Sun

Soil type

Sand or loam

Acidity

Not fussy

Moisture

Dry or normal

Size

0.4 m tall, 0.3 m wide

Hardiness

Frost tender: plant out after the last frost (mid-May)

Goes well with

• Zinnia: Just as fond of heat, with large flowers next to the small globes.
• Purpletop vervain: Airy purple clusters above the globes, also loved by butterflies.
• Strawflower: Another everlasting in warm colours for the cutting garden.
• Lavender: The same sunny, dry spot, and another plant for bees.
• Ornamental grasses: Fine stems add lightness between the compact globes.

Globe amaranth: when and how to plant it?

Plant in May–June.

1. Soak the seed overnight in lukewarm water and sow indoors in March–April in small pots or trays, at 20–25 °C.
2. Cover the seed thinly and keep the compost just moist; it germinates in one to two weeks.
3. Prick out the seedlings into individual pots once they have two true leaves, and keep them warm and light.
4. Harden the young plants off outdoors for a week in May and plant out after mid-May, when there is no more risk of night frost.
5. Set them at the same depth as in the pot, 25–30 cm apart, and water in well straight away.
6. Keep the soil just moist for the first few weeks until the plants are rooted.

Care

Watering

Water regularly after planting until rooted. After that only in long dry spells; plants in pots more often.

Feeding

A spadeful of compost at planting is enough. In pots, a little liquid feed every two weeks. Too much nitrogen gives lots of leaves and floppy stems.

Pinching

Pinch out the tips of young plants at 10–15 cm: they branch better and give more flowers.

Picking

Cut flowers regularly for the vase or for drying: the plant then keeps making new heads.

Deadheading

Remove brown heads back to the next pair of leaves or side shoot.

Tip: Wait for warm nights before planting out: globe amaranth put outside in a cold May stalls for weeks. In a pot on a warm patio it flowers most freely.

Globe amaranth: when to prune it?

When: An annual needs no pruning. Pinch the young plant soon after planting out and pick flowers all summer.

How:

• Pinch out the tips of young plants at 10–15 cm, just above a pair of leaves.
• Cut flowers with a long stem, just above a pair of leaves: new flowering side shoots grow from there.
• Remove faded, brown heads.
• Pull the plants up after the first frost and put them on the compost heap.

Pruning calendar and basic rules

Propagation

Seed

Sow indoors in March–April at 20–25 °C, after soaking overnight. You can save your own seed: in September let a few heads ripen fully, rub them out and store the seed somewhere dry and cool. Colours may differ from the parent plant.

Globe amaranth: how does it get through the winter?

Hardy to 5 °C: protect in harsh winters.

• Not hardy: it does not tolerate temperatures below about 5 °C and dies at the first frost.
• Clear the plants in October–November and sow again in spring.
• Store dried heads in the dark and dry: the colour then stays bright longest.

Diseases and pests

• Damping off: Seedlings collapse and rot at the base. Sow in clean compost, do not overwater and keep the air moving.
• Grey mould: Grey fluff on heads and leaves in wet, cool weather. Space the plants and cut away affected parts.
• Aphids: On young shoots. Spray off with water; ladybirds usually clear them.
• Root rot: Yellow, limp plants on wet, heavy soil. Choose a well-drained spot or a pot with a drainage hole.
• Slow growth: After a cold May it stalls for weeks. Only plant out once the nights are warm.

Through the year

• March: Soak seed overnight and sow indoors at 20–25 °C.
• April: Sow indoors. Prick out seedlings.
• May: Harden off. Plant out after mid-May.
• June: Plant out. Pinch young plants. Water until established.
• July: Flowering starts. Cut flowers for the vase.
• August: Full flower. Pick heads for drying.
• September: Flowering. Dry the heads. Let seed ripen.
• October: Last flowers. Clear the plants after the first frost.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Butterflies

Nectar for butterflies.

Did you know?

• The name amaranth comes from the Greek amarantos, ‘unfading’: the heads stay attractive for a long time, on the plant and dried.
• What looks like a flower is a ball of papery bracts; the true flowers are tiny and sit between them.
• In Nepal it is strung into garlands for the Tihar festival of lights.