Guided Tours with Garden Horticulturist

Hawaii Tropical Botanical Garden is now offering the experience of a special one-hour guided tour with our Garden Horticulturist.  Tours are offered on Monday, Wednesday and Saturday at 12:00 pm.  Regular admission fees apply though there is no added cost.

Posted in Education Programs | 2 Comments

Saving Rare and Endangered Palms

Palm Vista

Palm Vista at HTBG

Part of our mission at Hawaii Tropical Botanical Garden is to educate our visitors about the endangerment of the world’s rainforests and to acquire, preserve and propagate as many rare and endangered tropical plant species as possible to help ensure their survival for    future generations

The Garden’s Founders, Dan and Pauline Lutkenhouse,  have always been deeply concerned about the rapid  destruction of our world’s rainforests and tropical plants, and with good reason.  Nearly half of the world’s species of plants, animals and microorganisms live in the rainforest and are facing extinction due to unchecked deforestation.  In fact, twenty percent of the original rainforest is already gone and with it countless species have already been lost.

People have relied on tropical plants from the rainforest for building materials, medicinal purposes, nourishment and to beautify our living spaces. Today we also know that our rainforests slow global warming by storing massive amounts of carbon.

The high level of genetic variation or biodiversity that is  being lost is essential for species adaptability and continued species evolution.  The danger of this loss to the health of our entire planet and all living things cannot be overstated.

Here we will focus on just one small but valuable part of the rainforest that is being lost, the palm tree.  Palms are trees in the family Arecaceae,  sometimes referred to as Palmae. Palms are widely distributed in the tropical regions of the world, with some species venturing into subtropical or even temperate zones. The Palm Family has over 200 genera and 2,800 species.

Throughout our history, palms have been a most useful  resource. Leaves are used for thatching both the roofs and walls of houses. Leaflets are used for weaving mats, hats, baskets and other useful items. The stems of climbing palms such as Calamus, commonly called Rattan Cane, are used for furniture.  Palm sugar, palm wine, palm hearts and various fruits from a number of palms such as Date Palms and Coconut Palms provide us with food. Carnauba wax, used in automobile and furniture polishes, is produced from the leaves of the Copernicia prunifera palm.

During its thirty years in existence, the Garden has  endeavored to protect, propagate and display endangered palms for their unique beauty and to educate the public about their plight.

<i>Pelagodoxa henryana</i> (Marquesas Palm)

Pelagodoxa henryana (Marquesas Palm)

One such palm is the unique Pelagodoxa henryana,  commonly refered to as the Marquesas Palm.  It has large,    entire leaves up to 6.5 feet long and 3 feet wide and its trunk can reach over 20 feet high.  It is native to the Marquesas where it is found in dense rainforest, growing in narrow  ravines in humid valleys at low altitudes.  The ravine along our Boardwalk entry to the Garden matches these conditions exactly and you can see it is thriving there today.

We hope to see its first inflorescence soon which should bear unisexual flowers of both sexes, and can produce fertile seed.  This palm is now nearly extinct in the wild, with only one known population growing in a valley on Nuku Hiva, one of the Marquesas Islands in French Polynesia.

Carpoxylon macrospermum

Carpoxylon macrospermum

Another endangered palm is Carpoxylon macrospermum, a monotypic genus endemic to Vanuatu, a South Pacific   island chain. It was first described as Carpoxylon in 1875 from a specimen collected on the Vanuatuan island of Aneityum in 1859. Later attempts to find it on Aneityum failed. Thus, it was thought to be extinct until its accidental “rediscovery” on the Vanuatuan island of Santo in 1987 by Australian botanist John Dowe.

Since then, concerned conservationists in Vanuatu had the brilliant idea to market seeds of Carpoxylon and other palms worldwide to raise money to fund conservation activities.  Thus, the species has made a comeback in cultivation but is still critically endangered in the wild.   HTBG acquired and planted its first specimen in 1995 and it has reached a height of over 20 feet.  Because of its rarity it was planted in a hidden area, but today a more recently planted specimen can be seen near the end of the Boardwalk.

Carpoxylon macrospermum can grow up to 90 feet tall and its crownshaft is an amazing 4 to 5 feet tall!  The leaves are 12 feet long with leaflets 8 inches to 4 feet long.

Oncosperma tigillarium

Oncosperma tigillarium

Pictured to the left is Oncosperma tigillarium, commonly called Nibong Palm.

Native to South-East Asia, this clumping palm is covered in rings of downward-pointing black spines on the younger parts of the trunk.

Found in swampy areas near the coast, the Nibong can reach over 80 feet tall with a diameter of 6 inches.  The trunks are salt tolerant and the wood is used for house construction.

Our Garden sits on the ocean and has several specimens thriving in our collection.

Metroxylon americarum (Caroline Ivory-nut Palm)

Metroxylon americarum (Caroline Ivory-nut Palm)

Metroxylon amicarum, commonly called Caroline Ivory-nut Palm, is a beautiful palm endemic to the Caroline Islands in Micronesia.

This solitary palm grows up to 80 feet tall with spiny leaves.  The chestnut-brown, apple shaped fruit has a white ivory-like inside that can be polished and carved into decorative items and jewelry.

Dan Lutkenhouse planted 3 of these palms at the bottom of the Boardwalk Trail about 14 years ago. Today, you can not miss these 40 foot palms towering over the patch of  Temple Flowers below them.

Hydriastele rheophytica is a recently discovered palm which grows on the banks of rivers in New Guinea.  The name is derived from the Greek hydor meaning water and rheophytes which means growing in or near a stream.

Hydriastele rheophytica

Hydriastele rheophytica

This small, attractive palm grows up to 10 feet tall and has adapted to survive flood conditions by having very flexible stems and finely pinnate leaves which present very little resistance to water flow and let the palm bend with the  water rather than breaking.

This palm is planted in the Kahali’i stream-bed along the Boardwalk.

These palms are just a sample of the many rare and endangered tropical plants the Garden has striven to save and propagate over the years.

Unfortunately the destruction of rainforest habitat continues.   If we are to stem the tide of this devastation, then each of us must behave in an ecologically aware and responsible manner.  There are some simple things we can all do.

One is to recycle our aluminium cans.  This will reduce the need for bauxite, the source of aluminium, which must be mined from the ground in tropical countries.

Also we can use the power of the purse to lessen the demand for unsustainable goods and destructive  practices.  For instance, when purchasing tropical woods for furniture or construction, choose products that have been grown in a sustainable manner, or better yet, use recycled materials.

Finally and most importantly, you can share in the Garden’s mission!  Help us spread awareness of rainforest degradation and how each of us can help.

Posted in Arecacaceae, Conservation, Palms, Rare and Endangered | Tagged , , , , , , | Leave a comment

Garden Improvements – The Welcome Pond

Water Lilies thriving in the Welcome Pond

Water Lilies thriving in the Welcome Pond

The Garden is always growing and improving! Behind the Garden Entrance Gate was an area densely packed with various trees and impressive rock formations surrounding a natural blue-rock pond. In order to better highlight the pond and rock formations, several trees were removed to expand the viewing area. Garden staff excavated the pond and populated it with an array of eye-catching water lilies. All around the pond a beautiful groundcover Hemigraphis colorata was planted and several Medinilla magnifica are now perched upon the rocks, showing their bright pink flowers. Visitors now have a new feature to enjoy as they first enter the Garden. We call it the “Welcome Pond”.

The Garden has also added many Vireyas or Tropical Rhododendrons to its collection. Vireyas have exotic, wonderfully scented, vibrant flowers. Most of the 300 species grow in tropical but mountainous regions in New Guinea, Borneo, Sulawesi, Sumatra and the Philippines.

Many grow epiphytically (without soil) in tall trees in cloud forests and are cold hardy to about 40 degrees Fahrenheit. We have planted our Vireyas on the lava cliff side of the Boardwalk.

Posted in Garden Improvements, aquatic plants | Leave a comment

What’s Blooming? Couroupita guianensis – Cannonball Tree

Couroupita guianensis
See the slideshow in fullscreen
Common Name: Cannonball Tree

* class: Equisetopsida ( C. Agardh)

* subclass: Magnoliidae (Novák ex Takht.)

* superorder: Asteranae (Takht.)

* order: Ericales (Bercht. & J. Presl)

* family: Lecythidaceae (A. Rich.)

* genus: Couroupita (Aubl.)

Locality: French Guiana

The common name "Cannonball Tree" comes from its large, spherical fruits.

It has a cauliflorous habit, meaning both the fruit and the flower grow from stalks which sprout from the trunk of the tree.

Posted in Lecythidaceae, What's Blooming | Tagged , , | Leave a comment

The Garden’s Ginger Collection is in full bloom

June is an excellent time to see the Garden’s collection of Gingers, particularly the Honeycomb Gingers (Zingiber spectabile) See the slideshow in fullscreen.

Posted in Zingiberaceae | Tagged , | Leave a comment