Pittosporum, often called “pitt plant,” is a versatile evergreen shrub or small tree. These plants are chosen for their appealing foliage, which can vary in color and texture, and their often fragrant flowers. They provide year-round structure and visual interest, making them a popular choice for various garden designs due to their adaptability.
Understanding Pittosporum Varieties
Many Pittosporum varieties offer distinct characteristics for diverse garden applications. Pittosporum tobira, known as Japanese Pittosporum or mock orange, features glossy, leathery green leaves and clusters of fragrant, creamy white flowers. This variety is often used for hedges or as a specimen plant, with cultivars like ‘Variegata’ displaying attractive cream and green foliage.
Pittosporum tenuifolium, or New Zealand Pittosporum, is another widely cultivated species with many popular cultivars:
- ‘Tom Thumb’ (bronze-purple leaves, compact, dwarf habit)
- ‘Marjorie Channon’ (mid-green, often oval leaves)
- ‘Silver Sheen’ (delicate, silvery-green leaves, dark stems)
- ‘Golf Ball’ (naturally rounded, dense green shrub, minimizing shaping)
Pittosporum eugenioides, also known as Tarata, can grow into a large shrub or small tree with wavy-edged, yellowish to deep green leaves and fragrant yellow flowers.
Essential Growing Conditions
Pittosporum plants generally thrive in full sun to partial shade, with variegated cultivars typically showing their best leaf color in sunnier locations. They adapt to a range of soil types but perform best in well-drained, humus-rich soil. Proper drainage is important to prevent waterlogging, which can harm the root system.
Consistent moisture is beneficial for young plants as they establish their root systems, especially during dry spells in spring and summer. Once established, most Pittosporum varieties exhibit good drought tolerance, requiring less frequent watering. These plants are generally hardy in USDA Zones 9 to 11, tolerating temperatures down to about 0°C (32°F), though some tender species or those in colder regions may benefit from shelter from cold, drying winds or winter protection. A balanced, controlled-release fertilizer applied in spring and summer is typically sufficient.
Planting and Maintenance
Planting Pittosporum is best done in autumn or spring when the soil is moist and temperatures are moderate. Prepare the planting site by digging a hole at least twice the width of the root ball and to the same depth, ensuring the top of the root system is level with the surrounding ground. Mixing compost into the existing soil before planting enhances soil structure and nutrient availability. After positioning the plant, backfill the hole and water thoroughly to settle the soil around the roots.
For hedges or screens, spacing plants approximately 0.5 to 1.5 meters apart encourages dense growth. Applying a layer of mulch around the base helps retain soil moisture and suppress weeds. Pruning is important for shaping, controlling size, and maintaining plant health. Light trimming to maintain shape can be done throughout the growing season. More significant pruning to remove dead or crossing branches is best performed in late winter or early spring before new growth begins. When pruning for hedges, regular clipping two to three times during the growing season promotes a dense, even appearance.
Addressing Common Problems
Pittosporum plants can experience various issues, often linked to environmental conditions or pests. Yellowing leaves may indicate either overwatering, which can lead to root rot, or nutrient deficiencies, particularly a lack of nitrogen. Improving soil drainage and ensuring appropriate watering can address moisture-related yellowing. Browning leaves often point to underwatering, sun scorch, or cold damage, but can also be a symptom of root rot.
Common pests include aphids, mealybugs, and scale insects, which can cause distorted new growth or sticky residue on leaves. These can be managed with insecticidal soap or neem oil. Diseases such as leaf spot and powdery mildew are more likely in humid conditions with poor air circulation. Southern blight, a fungal infection, can occur in hot, humid environments. Addressing these problems involves correcting cultural practices like watering and air circulation, and applying appropriate treatments.