Siam Sublime Ornamental Ginger

Siam Sublime Ornamental Ginger (Curcuma alismatifolia 'Siam Sublime') is a summer flowering ginger that grows to about 60cm tall and only 40cm across, so a single pot on a courtyard table carries the whole display. Through the warm months it sends up slender stems topped with tulip shaped heads of pink and purple toned bracts that hold for weeks. Often sold as Siam tulip, it is one of the easiest tropical bulbs to grow once you accept that it sleeps through winter.

Why you'll love it

• Flowers that last. The colour comes from bracts rather than petals, so each head holds for weeks, and stems keep coming through summer.
• Small enough for a balcony. At 60cm by 40cm it suits a single 250mm to 300mm pot or the front of a shaded border.
• Built for humid heat. Humidity tolerant and heat tolerant, so it performs in the conditions that flatten most flowering perennials in the north.
• Very little work. Water and warmth through summer, then nothing at all over winter while the rhizome rests.

Where it works best

Pots and containers. This is the primary use. A 250mm to 300mm pot of free draining mix suits a clump, and a pot makes the winter dormancy easy: move it out of the rain and stop watering.

Balconies and courtyards. It gives tropical colour at a scale that fits a small space, and it does not need direct sun all day, which suits the partial light most balconies get.

Borders and feature planting. In frost free gardens, plant it in drifts at the front of a shaded bed among ferns and bromeliads.

Growing Siam Sublime ornamental ginger in Australia

Position and climate. Partial shade, or morning sun with afternoon protection. It suits tropical, subtropical and warm temperate gardens, and it is frost tender, so anywhere that frosts it must be grown in a pot that shelters over winter. Constant warmth drives the flowering.

Soil. Rich, free draining and open. A quality potting mix with extra perlite works in containers; in the ground, work compost through and raise the bed if drainage is doubtful.

Water and feed. Water once shoots appear in spring and keep the mix evenly moist through summer, never sodden. Feed a balanced liquid fertiliser every three to four weeks in growth, then stop watering once the foliage yellows in autumn.

Dormancy and dividing. The plant dies back completely over winter, which is normal and not a fault. Leave the rhizome dry and undisturbed and it will reshoot when soil temperatures climb.

What to expect when it arrives

This ginger is grown here as tube stock, so it arrives as a young plant with a developing rhizome rather than a clump in flower. Ordered outside the growing season it may arrive as a dormant rhizome with little or no top growth, which is the plant behaving as it should. Pot it up, keep it warm, and expect a first flowering the same or the following summer.

Plants are delivered Australia wide, with delivery from $29.95, and every plant carries our 30 day healthy plant guarantee. In cooler southern gardens, plan from the start to grow it in a pot.

Plant care guides and related reading

• Designing a tropical garden that holds up all year
• Browse the tropical plant range
• See what else suits growing in pots
• Compare plants for balconies and courtyards

Common questions

Why has my plant disappeared over winter?

It is dormant, not dead. The foliage dies back every year once temperatures drop, and the rhizome rests underground until spring warmth brings new shoots. Keep it dry through that period.

Can I grow it outside the tropics?

Yes, in a pot. It is frost tender, so in cool gardens grow it in a container that moves to a sheltered position over winter, then bring it back out once the weather warms.

How much sun does it need?

Partial shade suits it best, or morning sun with shade through the hottest part of the day. Harsh afternoon sun scorches the bracts.