How to Grow Billy Buttons in Australia

Billy buttons (Pycnosorus globosus), long sold as Craspedia globosa, is a native perennial daisy (Asteraceae) grown for golden globe flowers on tall, bare stems. It grows wild on inland plains and roadsides from Queensland to South Australia, and its heads hold their shape and colour for years once dried. The mistake most gardeners make is burying the fine seed, which needs light to germinate.

Three mistakes that matter

1. Burying the seed. Seed covered with a layer of mix often fails to appear, because light helps it germinate. Press it firmly onto the surface of moist seed raising mix and add no more than a fine dusting of vermiculite.
2. Letting water sit around the crown. The plant copes with heavy soil and brief winter wet. Soggy ground or thick mulch against the crown can rot it, most often in humid summers. Choose an open, free-draining spot and keep mulch thin.
3. Feeding it like a bedding annual. Rich feeding and shade produce soft, leafy growth, floppy stems and fewer flowers. Give it full sun, a lean diet and low-phosphorus products, as set out under Care by growth stage.

When to plant

Seed germinates at 21 to 24°C, so warmth decides the start. Sow while days stay warm, in autumn or spring in most zones, or start trays earlier on a seedling heat mat. One sowing is enough: each plant forms a clump that flowers from early spring into summer for a few years.

In frosty gardens, start trays indoors about six weeks before the last frost and plant out once it passes. In the tropics and subtropics, sow early enough for plants to flower before humid summer weather arrives.

Site, soil and setup

Billy buttons stays in one place for years, so it needs no yearly rotation. For ground that stays soggy, read about waterlogged garden soil before planting.

Container growing

The silver rosette and tall gold stems suit a deep pot on a sunny deck. Give one plant a deep pot, around 25 cm wide and deep (about 8 L), with generous drainage holes. Fill it with native potting mix, adding coarse sand or perlite if the mix feels heavy.

• Watering. Pots dry out faster than beds, so check them often through spring and summer. Never leave the pot standing in a saucer of water. See watering pots through summer.
• Feeding. Give worm casting liquid, diluted to weak tea colour, every fortnight from spring until flowering ends.
• Position. Full sun, with open air around the plant in humid gardens.

Sowing Seeds

Start billy buttons in trays or cells, where the fine seed stays lit, warm and safe from snails.

Starting under cover

• Fill a cell tray or punnet with fresh seed raising mix, firm it and water it before sowing.
• Sow two or three seeds per cell, so each seedling moves on later without its roots being torn apart.
• Press the seed onto the surface, as in sowing tiny seeds, then mist it or water the tray from below.
• Keep the tray at the warmth under When to plant, in bright light out of direct sun, under a clear cover.
• Lift the cover once seedlings appear, and thin each cell to the strongest one.
• Seedlings can trickle up over several weeks, so do not tip out a tray too early.

Sowing direct

Seed can go straight into a fine, weed-free bed once the soil is as warm as under When to plant. Press it onto raked soil, keep the surface moist with a fine spray and thin seedlings to the spacing in the table above.

Transplanting

Billy buttons resents root disturbance, so move each seedling with its whole root ball. Harden seedlings off first (a week or so of gradually longer spells outdoors that toughens soft growth), as in hardening off seedlings. Plant in groups at that spacing, at pot depth, and water in with seaweed solution at 30 mL per 9 L.

Care by growth stage

Steady moisture while young, sharp drainage and a lean diet decide how well billy buttons flowers. It needs far less feeding than annual cut flowers, and phosphorus-rich products are best left out.

Weeks count from sowing. If growth stalls in poor soil, scratch in a light dose of controlled release granular made for native plants, labelled low in phosphorus, each spring.

Deadheading

Removing spent heads keeps new flowers coming, and a tidy-up after flowering keeps the clump dense.

• Snip each browned head off at the base of its stem while the plant is flowering.
• Pick for the vase often, because picking does the same job as deadheading.
• Once flowering ends, cut every remaining stem back to the base.
• Trim old leaves that turn untidy or die down, but never cut into fresh growth in the centre.
• Leave a few heads to ripen on the plant if you want to save seed.

Companion planting

Billy buttons suits a sunny native or cottage bed beside plants that share its drainage and leave its crown in open air. Its flowers also draw bees, butterflies and other beneficial insects.

Grows well with

• Everlasting daisies, native paper daisies that share the same sun, soil and drying use.
• Brachycome, a low native daisy that edges the bed without crowding the clump.
• Statice, another dried flower that likes the same sunny, free-draining bed.
• Native grasses, whose fine leaves set off the round gold heads.

Keep apart

• Sunflowers and other tall, dense plants, which shade the clump and soften its stems.
• Mint and other fast spreaders, which overrun a slow clump.
• Lettuce and other soft seedlings, which draw snails and slugs to the same bed.

Harvesting and Drying Blooms

Cut billy buttons once each ball is fully round and evenly golden, before any of its tiny florets open.

• Cut in the cool of the morning with sharp secateurs or snips.
• Take the longest stem possible, cutting at the base, so picking also deadheads.
• Strip the lower leaves and stand fresh stems in a clean bucket of water straight away.
• To dry, tie small bunches and hang them upside down somewhere dark, dry and airy.
• Or stand stems upright in an empty vase, where they dry in place.

Keep fresh stems in a cool room and change the water every few days.

Use billy buttons fresh in native posies, or dried in everlasting arrangements beside paper daisies and grasses.

Common problems

Seeds did not come up. Buried seed (see Three mistakes that matter), a tray that dried out or one kept too cool are the usual causes. Read more

Pale, stretched seedlings. Seedlings raised in poor light stretch and flop before they reach the garden. Read more

Seedlings sulk after planting out. Torn roots set the plant back, so move each seedling with its root ball intact. Read more

Plant collapses at the base. Root or crown rot takes hold where water sits around the crown, and an affected plant seldom recovers. Read more

Floppy stems and few flowers. Too little sun or too much feed gives soft growth; move the plant into full sun and feed lightly.

Plant fades after a few years. It is a short-lived perennial, so sow fresh seed every few years, or take cuttings from a good plant as under Tips.

Pests and diseases

Snails, slugs and aphids cause most of the damage, and seldom badly on a plant in full sun.

Common garden snail (Cornu aspersum). This introduced snail, found in every state and territory, chews young leaves and seedlings at night, and slugs do the same. Sink shallow beer traps into the soil or ring pots with copper tape. Read more

Aphids (family Aphididae). These small, soft-bodied insects cluster on new growth and developing flower stems, sucking sap and leaving sticky honeydew. Hose them off, or spray horticultural oil or soapy water, but not in hot weather. Read more

Damping off (Pythium species and Rhizoctonia solani). These soil-borne pathogens rot seedlings at soil level, so they collapse in the tray, most often in wet mix. Read more

Prevention first

• Sow in fresh seed raising mix in clean trays, and lift the cover once seedlings appear.
• Keep to the spacing under Sowing Seeds, so air moves around each crown.
• Check new growth and flower stems each week from spring.
• Clear leaf litter and rubbish where snails and slugs hide by day.

Tips

1. Take cuttings from healthy growth of your best plant; they root quickly and carry it on after the parent fades. See taking cuttings.
2. Plant against green foliage, where the silver leaves and gold heads stand out most.
3. Collect seed from a ripe head: each seed carries a small plume of feathery hairs, so pick it on a still, dry day.
4. Common billy buttons (Craspedia variabilis) is a different, shorter plant that shares the common name; check the botanical name when buying.