Achyranthes in Hawaiian Culture: Today, no one seems to know the Hawaiian name for Achyranthes. This is indeed sad because with the lost of a plant’s Hawaiian name, its uses and mo‘olelo (stories) also disappear. Today, people have begun calling Achyranthes the ‘Ewa hinahina. This is appropriate since it once occupied much of the ‘Ewa Plains and the tiny white hairs on its leaves give it a silvery or grey color.
Collecting Seeds: The spikes of utricles (a thin-walled fruit containing one seed) ripen in late summer and early fall. Avoid the temptation to collect more utricles than you need. And, to maintain genetic diversity in your garden, it’s better to collect five utricles from ten plants than 50 utricles from one plant. The utricles store well in a refrigerator for future use.
Growing from Seed: Planted in any clean, well-drained media, Achyranthes seeds easily sprout in about two weeks after an overnight soaking in tapwater. (Soak and sow the whole utricle; it’s not necessary to remove the seed within.) Not all seeds are viable, so, it’s a good idea to sow 2-3 utricles per container, or you can sow everything in a single tray and transplant the seedlings. Seedlings grow pretty rapidly and will grow even more quickly if lightly fertilized. However, it’s important to keep the seedlings in full (or nearly full) sunlight. Otherwise, they will grow spindly with poorly adapted leaves (i.e., green instead of silvery leaves). The plants should reach six inches in height in about six months. The seedlings are susceptible to mealybugs and scale insects; bad infestations will kill them.
Growing from Cuttings: It is almost too easy to grow this plant from cuttings. Plant 4-6 inch cuttings in any clean, well-drained media. Treating the cutting with rooting hormone is probably a waste of money, but you can do it if you like. Place individual cuttings in a small humid container such as a clear plastic cup with lid; a group of cuttings can go into a larger clear storage container. Keep the container in bright light but not direct sun (to avoid overheating) and the cuttings will begin rooting in about a week. (Cuttings will also root under a misting system but be careful the leaves don’t begin to rot.) Wait another 1-2 weeks before removing the rooted cuttings from the clear container. Out of the container, they should be transitioned to full sunlight. Wait another month before transplanting them to a larger container or into the garden.
Growth in the Garden: Achyranthes will grow in about any soil type but do best in well-drained calcareous or cinder-rich soils. They can reach 1-2 foot in height in less than a year and 3-6 feet tall in two. They will begin flowering and fruiting within one year. They are not long-lived plants, lasting two to, maybe, ten years. They actually seem to live longer if you torture them with no watering and no fertilizer. In fact, the longest-living plants I’ve seen are wild plants in Kalaeloa whose trunks are restricted to a tiny hole through a large slab of exposed reef rock.
Diseases and Pests: Achyranthes adults remain targets for mealybugs and scale insects. The mealybugs can cluster at the stem and flower tips. Or, they can infest the roots. Scale insects are usually seen on the stems and leaves. Please refer to the Enemies in the Garden webpage for ways to combat these pests. A particularly nasty scale is a brown, hard-shelled type (see photograph) that reproduces rapidly and can kill your plant in 1-2 weeks. Pruning off the infested branches and treating the remaining plant with horticultural oil and a systemic pesticide works best on this villain. Achyranthes are also susceptible to root-knot nematodes and pathogenic fungus in the soil. Treating these successfully is very difficult. Usually, the best 'cure' is to find another distant location in your garden and try again. Finally, don’t confuse the short lifespan of Achyranthes for a disease or pest problem in your garden. If you want to display this plant for a long time, you’ll need to occasionally replant new plants to replace the senescent ones.
Ā ā Ē ē Ī ī Ō ō Ū ū