Costus, also known as Gingerland Costus, is a captivating plant with stunning spiral-shaped inflorescences in vibrant shades of red and orange, adding a touch of exotic beauty to your garden. Easy to care for and hardy, it's an excellent choice for your Auckland garden.
Planting Calendar
The best time to plant Costus is during the warmer months, typically in late spring to early summer, when the risk of frost has passed and the soil has warmed up.
Prepare
The ‘Fiery Costus’ or ‘Spiral Flag’ plant is a tropical evergreen growing to around 60cm, with attractive spiralling stems and smooth, dark green leaves. In India it is known as the ‘Insulin Plant’ and used in the treatment of diabetes. In the warm months they produce beautiful orange flowers on cone-like heads at the tips of the branches. Ideal for use in tropical gardens and can also be grown in pots.
Position
Plant in partial shade, with some shelter from cold winds and frosts.
Soil
When planted into the ground Costus prefers a free-draining soil that is rich in organic matter. To improve the organic content in your soil, break up the soil and add Kings Compost and Kings Sheep Pellets then mix together well. When growing in containers, plant into Kings Container mix. This mix contains Saturaid, which helps with moisture retention in the soil.
Plant
When planting into the ground, ensure the plants is well watered then, gently tap the plant out of its pot. Dig a hole twice the depth and width of the plant’s root ball. Mix Kings Compost into your existing soil at a 50/50 ratio, add Kings Sheep Pellets then mix together. Backfill the hole with this soil, so that when planted the top of the plant’s roots sit level with the surrounding ground. Firm the soil down gently and water in well with Aquaticus Organic Garden Booster. In heavier clay soils, where drainage is likely to be an issue, plant onto a raised mound and sprinkle Gypsum Clay Breaker into the bottom of the hole, this helps slowly condition the soil and help to break down the clay. When planting into containers plant into Kings Container Mix, as this has water retention crystals in it, which will help in keeping the soil moist.
Care
Watering
Costus likes constant moisture, so not allow it to dry out. Water slowly, allowing the water to sink down into the roots, rather than just allowing it to run off the top of the surface of the soil, aiming to keep the soil moist during hot periods. Add Saturaid into the soil at planting time, as this helps to channel water down to the roots where it is needed the most.
Feeding
For strong healthy roots and plants, apply monthly applications of Aquaticus Organic Garden Booster, from spring through to the end of autumn, this encourages root growth and increases the microbial activity in the soil. Monthly applications of Kings Sheep Pellets will help with soil conditioning and plant health.
Protecting
Protect from slugs and snails by applying applications of Quash around the base of the plant. Re-apply after rain.
Mulching
Mulching around plants can help conserve moisture, regulate soil temperature, and reduce weed growth. Mulch around the base of the plants (making sure it is not in direct contact with the trunk or base of the plant) with Living Earth More than Mulch. Replenish mulch each spring.
Spraying
Pests and disease are not a issue when growing Costus.
General Care
When using sprays, chemicals or fertilisers always read the label and follow the instructions carefully. Apply sprays in the evening to avoid harming beneficial insects.
Expert Tip
Avoid wetting flowers when watering as they are easily damaged and can turn to mush.