Grevilleas, a diverse genus of Australian native plants, offer American gardeners an opportunity to cultivate unique, drought-tolerant, and wildlife-friendly specimens. Their incredible range of forms, from groundcovers to trees, and their exotic, spider-like blooms make them exceptional additions to warm-climate landscapes. Selecting the right variety is key to success, as their suitability varies significantly across USDA hardiness zones, primarily thriving in zones 9-11.
This cultivar is arguably one of the most popular and reliable for American gardens. As a dense, mounding shrub, it typically reaches 4-6 feet in height and spread, making it perfect for borders or as a focal point. Its main attraction is the prolific display of large, coral-pink to deep red flower clusters that appear nearly year-round in frost-free climates. The plant is highly adaptable to various soil types, provided they are well-draining, and demonstrates excellent heat tolerance. It thrives in full sun and requires minimal watering once established, making it an ideal choice for water-wise gardens in California and the Southwest.
For gardeners seeking a plant with fine, textural foliage reminiscent of rosemary, this species is an excellent selection. It forms a graceful, arching shrub up to 6 feet tall and wide. The needle-like, dark green leaves provide a beautiful backdrop for the abundance of small, spidery red flowers that attract hummingbirds throughout the cooler months. It is notably cold-hardier than many other grevilleas, tolerating brief dips into the low 20s (°F), which expands its potential range. It demands excellent drainage and full sun to perform its best and is resistant to deer browsing.
For a larger architectural statement, ‘Long John’ is a spectacular choice. This large, open shrub can reach 10-12 feet in height and width. It is celebrated for its long, elegant, toothbrush-shaped flower clusters in a vibrant coral-red hue, which are a significant nectar source for birds. Its growth habit is fast and vigorous, making it suitable for use as a quick screen or windbreak. It performs exceptionally well in hot, dry, and sunny locations but is less tolerant of humidity and heavy clay soils than other varieties. It is best suited for zones 9b-11.
This prostrate form is the perfect solution for groundcover needs, cascading over walls, or spilling from containers. It remains low, typically under 1 foot tall, but can spread several feet wide. Its small, gray-green, needle-like foliage offers a soft texture, and it produces tiny, red and cream flowers sporadically throughout the year. ‘Coastal Gem’ is particularly valued for its resilience to coastal conditions, including wind and salt spray. It is also one of the more cold-tolerant varieties, handling temperatures down to around 15°F when established, suiting it for gardens in the Pacific Northwest.
A truly aptly named hybrid, ‘Superb’ is renowned for its breathtaking and large bird-attracting flowers. The blooms emerge gold, age to orange, and finish with pink tones, often presenting all three colors on the shrub simultaneously. It forms a well-branched, rounded shrub to about 5 feet tall and wide. Like most grevilleas, it requires full sun and perfect drainage to avoid root rot. It flowers heaviest from late winter through spring but will often produce blooms in other seasons. Its spectacular floral display makes it a prized centerpiece in any suitable garden.
