Tropical Gardening: Rare palms abound in Hawaiian gardens

Are you interested in conservation?

How about learning more when it comes to Hawaiian palms?

We have at least 24 species of endemic Pritchardia, or loulu, all of which are endangered and could become extinct without our help. Then there are thousands of palm species worldwide that are endangered because of habitat loss. Many have been introduced to Hawaii by our botanical gardens, nurseries such as Jeff Marcus’ Floribunda Palms and the International Palm Society. In fact, we probably have more palm species here than any other place in the United States.

The good news is that our Hawaii Island Palm Society is anxious to share rare species with those interested by inviting folks to the annual BBQ Dinner and Rare Palm Auction from 5-9 p.m. Friday, Feb. 9, at Aunty Sally’s Luau Hale in Hilo.

The event also will include a special talk by Tom Mirenda of Hawaii Tropical Botanical Garden.

If you plan to attend, it is important to RSVP by Friday (Feb. 2). If you have questions, call treasurer Stephen Kling at 960-9388 or email stephen@backyardeden.com.

By joining the International Palm Society, the whole world of palms is open to you.

Every two years, the society sponsors an educational trip to exotic locations. This May, the society plans to explore the jungles of Colombia. In 2020, members will head to the remote island of Reunion in the Indian Ocean.

For more information, check out the society’s website at internationalpalmsociety.com.

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Hawaiian Pritchardia actually evolved here and are found growing naturally only in Hawaii. At one time, there might have been many dozens of species, but with the introduction of the Polynesian rat and pig, many must have died out.

Later introduction of grazing animals did further damage, so now there are only remnants of what must have been vast populations of the loulu.

Of some 28 species of Pritchardia in the world, 24 are natives of Hawaii. The remainder are found on a few islands in the South Pacific.

Two new South Pacific species were only recently discovered. It is a shame that many of these species have declined in number to the point that they are almost extinct.

For example, the Kona loulu, or Pritchardia maideniana, is a tree from Puna, Kona and Ka‘u. These palms were at one time found abundantly from Kalapana along the coast to Punaluu and the Kailua area, a distance of more than 150 miles.

Today, only occasional isolated specimens can be found. Few seedlings appear around the parent plants. Without man’s help, they, too, will disappear.

Otto and Isa Degner published an article in June 1971 in “Phytologia” (Vol. 21) that speculates as to why the decline. They wrote that on the Island of Hawaii at Kaliilii, near Wahaula, within Hawaii Volcanoes National Park, a few impressions of prostrate trunks can be seen on a prehistoric, though not very old, pahoehoe lava flow.

Beyond the Southwestern boundary of the national park, between the main road and the ocean, at Kawaa, lies an expanse of prehistoric, smooth pahoehoe. Here, the pahoehoe had gently flowed through a palm grove, the wet trunks burning slowly through the base so the trees fell helter-skelter upon the cooling lava.

The writers are convinced that the loulu reached the Hawaiian Islands some eons ago and might have more or less encircled many stretches of the islands with extensive groves, particularly before the Polynesians bought the pig and perhaps, as a stowaway, the seed-eating Polynesian rat. The fossil impressions at Kaliilii and above all at Kawaa are irrefutable proof of this fact.

By 1969, the Pritchardia maideniana was possibly within a few years of extinction along the Ka‘u coastline unless measures were taken to ensure its survival. Fortunately, C. Brewer and Company, Ltd., the major landholder in Ka‘u had just embarked on a resort development in the region and was developing a large nursery to supply materials for landscaping the project.

The company was interested in locating and propagating plants adaptable to this dry, windy region. It was thought that the native plants of the region should have first consideration since they proved their worth under Ka‘u’s climatic conditions.

In 1970, seeds of this palm were collected at the Beamer home adjacent to Punaluu Black Sand Beach. The seeds were planted in flats and grown to landscape size. Today, several groves are beautifying the Punaluu area of Ka‘u.

Trees from this batch of seed also found their way to the King Kamehameha Hotel, Kona Outdoor Circle garden and many other sites around the island. Seeds distributed by the Hawaii Island Palm Society to California and even southern France have been found to do well in protected locations.

Pritchardia maideniana is rarely found in the wild and only occasionally in the landscape. The most common types are two introduced species from the South Pacific. These are Pritchardia thurstonii and Pritchardia pacifica.

“Thurston’s Loulu” is noted for flower clusters up to 6 feet long. Pritchardia pacifica has very large leaves that were used in the old days as sunshades and umbrellas.

These species are adapted to dry coastal locations. Pritchardia maideniana prefers sunny drier locations but has been grown at elevations as high as 3,000 feet.

Another rare one is named after George Schattauer, Kona kamaaina. A few trees are found above Kaohe, Honomalino and Hookena. This species and Pritchardia beccariana from the Kulani prison road near Volcano are being distributed on the Big Island.

It’s important to the survival of many of these beautiful species to use them in our gardens. Unfortunately, many nurseries do not carry the native loulu, and the seed of some species are difficult to obtain.

Amy Greenwell Ethnobotanical Garden has a good collection of species. If interested in obtaining seed, contact Peter Van Dyke at the garden.

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To propagate loulu palms, plant fresh seeds in flats or shallow boxes filled with soil. Cover the seeds with 1/8 of an inch to 1 inch of soil, depending on the size of the seed.

Keep the soil in the flats moist but not wet. Fungi that cause damping off are likely to ravage the tiny seedlings if the soil is kept soggy.

Seed flats may be covered with clear plastic to keep in warmth and moisture. This will speed up germination.

Be sure to keep seed and seedlings protected from rats.

Germination time of palm seed varies widely with the species and requires patience. They might not peek out of the ground for several months following planting.

Pot the plants into 1-gallon containers after they sprout. A suggested potting mixture is equal parts of soil or cinder and rotted compost.

Fertilize monthly with a complete fertilizer. When the seedlings are 1 to 2 feet high, transplant them to 3-gallon containers or plant them in the ground.

Loulu palms are well-suited for planting in groups, as specimens, or for lining driveways.

Young palms require coddling until established. Then, they thrive with very little attention other than sun, fertilizer and water.

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If you want to get involved with efforts to bring back our unique Hawaiian plant life by learning even more about our loulu and other natives, the upcoming Nahelehele Dryland Forest Symposium is just around the corner.

It is scheduled from 9 a.m.-5 p.m. Feb. 9 at the King Kamehameha Kona Beach Hotel in Kailua-Kona. Register by Tuesday (Jan. 30) to get the kamaaina discount.

Call Kathy Frost at 325-6885 for details.

The University of Hawaii Palamanui Campus in Kona also is offering a series of hands-on classes and workshops titled Restoring Kona and led by Richard Stevens. This is an opportunity to get involved in restoring ancient trails and re-establishing native species.

To register, call UH-Hilo’s College of Continuing Education and Community Service at 932-7830.

Remember, if folks begin to show interest in rare plants such as the Hawaiian Pritchardia, our nurseries can then afford to carry them as part of their regular stock. These palms and many other native plants should be used in the Hawaiian landscape.

It is up to us to make it happen.