I’ve been interested in Australian plants since my early days in horticulture. The flora of The Land Down Under has evolved to survive in harsh conditions that include drought and poor soil nutrient levels including very low levels of the element phosphorous. There are many genera that are beautiful and useful in ornamental horticulture, especially in USDA Zones 7-9. One genus I’m particularly fond of is Grevillea, which boasts some 360 species all from Australia and Indonesian islands that lie east of the Wallace Line, which delineates the faunal boundary that separates the ecozones of Asia and Australia. Grevillea flowers are beautifully ornate, frilly and colorful. I post many flower photos on social media, and Grevillea gets more likes than any other genera.
Grevillea can be generally characterized as evergreen shrubs, but there are groundcover forms as well as some tree species that can reach over 100 feet high. For USDA Zones 8-10, there are a plethora of stunning forms of Grevillea. In Zone 7, the choices are a bit more limited but there are nonetheless some fabulous flower forms. Grevillea victoriae is hardy in Zone 7 and has beautiful frilly orange flowers. I visited the Gerdemann Botanical Preserve in Yachats, Oregon, in mid-February this year and the G. victoriae was blooming nicely. We are growing Grevillea lavandulacea ‘Penola’ and G. ‘Noellii’ in our landscape at Little Prince of Oregon Nursery where we’ve had two winters in a row with low temps staying above 20°F and both of these plants are doing beautifully. I have a G. rosmarinifolia in my landscape in Albany, Oregon, that has gone down to 8°F with no damage. Perhaps the hardiest is G. australis, which handles temperatures of 0-5°F without damage. It blooms in early spring and has delightfully sweet-smelling diminutive flowers.
If you’re lucky enough to live in USDA Zones 8b-10, a whole world of amazing Grevillea selections are at your fingertips. I visited the private garden of Rich Ouellet, a sales representative for Fleurizon in Southern California. Rich has an amazing garden north of San Diego, California, containing many Grevilleas, which were blooming profusely when I visited last October. This is truly a genus that merits more attention in ornamental horticulture.
Why grow Grevillea?
- The flowers are unique and beautiful.
- The genus is heat and drought tolerant.
- It's deer and kangaroo resistant.
- It grows in nutrient-poor soil.
- Attractive to birds, bees and other pollinators.
Mark Leichty is the Director of Business Development at Little Prince of Oregon Nursery near Portland. He is a certified plant geek who enjoys visiting beautiful gardens and garden centers searching for rare and unique plants to satisfy his plant lust. firstname.lastname@example.org