Barleria greenii is a fast-growing, attractive shrub that can be successfully propagated by seed and cuttings. It grows best in well-drained soil, in full sun to partial shade, and warm, humid conditions, making it ideal for gardens in subtropical and tropical regions. To grow this species from seed, harvest ripe seed capsules before they burst open, as the plant disperses its seeds explosively. Allow the seeds to dry in a cool, dry place. Sow them in early spring or summer in a mix of two parts quality soil, one part compost, and one-part coarse river sand. Press the seeds lightly into the surface of the soil without covering them. Place the tray in light shade (around 40%) and keep the soil moist using a fine mist spray. Maintain temperatures between 20–25°C. Germination usually occurs within 7 to 28 days. When the seedlings reach a height of about 150–200 mm, they can be transplanted into their permanent positions in the garden.

Cuttings are another effective method of propagation. Take 10–12 cm long softwood or semi-hardwood cuttings in summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cuttings in clean river sand or a sandy loam mix in a free-draining pot or tray. Keep them in a warm, humid environment with bright, indirect light, ideally between 20–25°C. Roots typically form within 4 to 6 weeks. Once rooted, transplant them into pots with compost-rich soil and harden them off before planting them outdoors.

Barleria greenii thrives in full sun but can tolerate light or dappled shade, especially in very hot areas. Plants grown in deep shade tend to be weak and flowers less. It grows well in loamy, sandy, or clay soils, provided they are well-drained. The ideal soil pH is slightly acidic to neutral. Avoid waterlogged conditions, as they can lead to root rot. Adding compost to the soil helps improve its fertility and structure. During hot and dry periods, water the plant twice a week to keep the soil evenly moist. In cooler seasons, watering can be reduced, but the soil should never be allowed to dry out completely. A balanced fertilizer containing equal parts nitrogen, phosphorus, and potassium can be applied every three months during the growing season. Organic compost can also be used, but avoid overfeeding, particularly with high-nitrogen fertilizers. Applying a thick layer of mulch around the base of the plant helps retain soil moisture, regulates temperature, and suppresses weeds. In summer, mulch keeps the roots cool, and in winter, it helps to insulate them. This shrub grows quickly and can reach 1 to 2 m in height. If not pruned, it may become woody and lose its shape. Prune back by up to two-thirds in late winter or early spring to encourage bushier growth and more flowers.

Barleria greenii is ideal for garden beds, borders, rockeries, and along pathways. It looks best when planted in groups of three to five, allowing space for each plant to spread naturally. It also performs well in large containers placed in sunny courtyards. It pairs beautifully with other drought-tolerant and sun-loving species such as Helichrysum petiolare (for silver foliage), Bulbine frutescens (as a succulent groundcover), Leonotis leonurus (for bold colour contrast), and Crassula ovata (for leaf texture). These companions not only share similar soil and light preferences but also contribute to a vibrant, low-maintenance, and pollinator-friendly garden.

Barleria greenii is largely pest-free, making it a low-maintenance option for gardeners. However, young seedlings may be susceptible to damping off in overly wet conditions. To prevent this, ensure good air circulation, avoid overwatering, and use general fungicide if necessary.