Growth Requirements
General
My (Koebele) experiences growing ʻālaʻa are similar to those growing kōlea lau nui (Myrsine lessertiana); not too difficult to sprout from seeds or grow in a pot (up to about a foot [30 cm] tall), but consistently dying whenever I planted them in the ground. Fortunately, a few people have had better success than me (see photographs above and discussion below). However, growing ʻālaʻa to maturity in a cultivated landscape remains a challenge.
The reason(s) all my ʻālaʻa plantings died was either because of the soil or temperature (or both) at my planting sites. In a couple of instances, the restoration site I planted them in was just too dry for the young ‘āla‘a; they lasted less than a year. For the other plantings, in cultivated settings (all less than 500 ft [152 m] elevation), each one (sometimes slowly, sometimes rapidly) declined in health despite my attempts to help it with increased watering or fertilizer. I rarely found any above-ground pests on these small ‘āla‘a — scale insects mostly — and these were always quickly eliminated, either by hand or with horticultural oil and/or a systemic insecticide. Below ground, I don't know what was happening, but it wasn't good, and in a year or less my ʻālaʻa would be dead. (If I had been smarter at the time, I would have sent samples to the University of Hawai‘i at Mānoa Agricultural Diagnostic Service Center to see if they could determine the cause of death). I have never tried to keep ʻālaʻa for more than one to two years in a pot, so I cannot say for certain how they would have fared if I had kept transferring them to larger and larger containers; my largest potted ʻālaʻa before planting them in the ground were a little over a foot (30 cm) tall. David (Eickhoff) has commented that ʻālaʻa do not make good potted plants because their roots tend to coil, and the plant will go into decline if not planted out.
Obviously, from the online photographs reposted above, others have had more success with ʻālaʻa than me, one of them being Anna Palomino, a friend, and the manager of and horticulturist at the State of Hawai‘i Olinda Rare Plant Facility on Maui. Anna says that the 4-year-old ʻālaʻa in the photograph above is one of several she planted that are today (2026) about 15 years old and 12 to 15 feet (3.7 to 4.6 m) tall. Surprisingly, and somewhat discouragingly, none of these 15-year-old trees have yet flowered.
So what explains Anna's success and my failure — other than her amazing talent at growing even the most difficult native Hawaiian plants? (Check out this NTBG article about Anna's success with one of the rarest and most difficult-to-grow native Hawaiian plants, Kanaloa kahoolawensis.) Well, two environmental differences come to mind. One, Olinda is in upland Maui, so the temperature there, particularly the soil temperature at night, is quite a bit cooler than anything my ʻālaʻa encountered. Second, and this is more difficult to prove, the soil at Olinda (and on Maui in general) is likely less contaminated with pests and pathogenic soil microbes than the urban O‘ahu lowland soil I planted my ʻālaʻa in. Therefore, until there is more horticultural research, my advice to anyone wishing to grow ʻālaʻa is to plant (or keep) it: (1) in the coolest soil/location you can find, and (2) the "cleanest" soil or media you can find or maintain (i.e., a 'wild' site or elevated pot). Below is a bit more advice I can share about the horticultural requirements or preferences of ʻālaʻa based on my field observations and cultivation experiences.
It's important to know which species of ʻālaʻa you have, since this will determine how much watering your plant will require. If you have a Planchonella spathulata, you'll not have to water it much (or, perhaps, at all, depending on the climate of your landscape) after it establishes its roots in the ground. Water it weekly for about six months during this establishment period. If your landscape is periodically hot and dry, you'll also likely need to water your established ʻālaʻa during these dry period(s) to prevent leaf loss. If you have a Planchonella sandwicensis, commit yourself to always keeping the soil surrounding your ʻālaʻa moist. Obviously, how much you will need to water your planting site to do so will depend on the climate of your landscape's location.
Both species of ʻālaʻa do well in a site with full sunlight for all or most of the day. Planchonella sandwicensis is more shade-tolerant, and plantings of both species do better if they are shaded from the midday sun when they are small (i.e., less than 2 ft [61 cm]). Given that the healthiest wild ʻālaʻa I've seen were nearly always growing either on a slope or in a lava field, make sure the soil surrounding your plant drains water easily.
ʻĀlaʻa, both in pots and in the ground, grow slowly (about a foot [30 cm] or less per year), so be patient. While I never saw any positive results from fertilizing my in-the-ground ʻālaʻa, I also didn't see any harm in doing so. For potted ʻālaʻa, we've always applied either a balanced controlled-release granular fertilizer every six months, or used a liquid organic or inorganic fertilizer at about one-third the recommended strength every one to two months.
Pests and Diseases
Few pests seem to attack ʻālaʻa, perhaps because of its milky sap. However, sap-sucking insects, most often scale insects, and occasionally aphids and mealybugs, may get established on the stem-tips and leaves. Lilleeng-Rosenberger [2005] has reported problems with black twig borers. Refer to the Pests & Diseases page for ways to deal with these pests.
