Miniature Forest Revolution

The Miyawaki method

By Heidi Bornhorst

Koa trees, Loulu palms, mulch dishes Ho`omaluhia

Aloha Hawai`i Gardeners: are we ready to plant and nurture a miniature forest Revolution?

I have wanted to learn about the Miyawaki method for a while. Thanks to generous friends: Chirstine and Pokey, I got my hands on one of the books about the Miyawaki miniature forest method, and plunged in.

The book I just read is called, “Miniature Forest Revolution”, by Hannah Lewis. 

Developed in Japan and now spread around the world this is a new and akamai way of forest restoration.

Dr Akira Miyawaki was a Botanist, ecologist, and researcher. He networked with others in Japan and around the world to plant mini climax forests and nurture them. 

I have advocated for years, to simply plant a tree, nurture a garden, keep one plant alive, Volunteer at a garden.  Go hiking, learn about our Hawaiian forest. Nurture our Hawaiian forests and learn more. 

Learn about and nurture our living soils.

This is a new way to do it and is very inspiring.

Trees and forests really do heal our land. Compost really does work. Watersheds can be restored by the forest. Healthy forests of multi layers cover the soil and nourish it. 

Koa tree and Uluhe ferns

With plants covering soil and adding their leaves to the living soil mix, we have less runoff when it rains.

We like to keep soil alive and where it belongs: on Land

When soil washes into the ocean after heavy rains we have fresh water killing the reef and silt and mud smothering the reef, clouding the water and adversely affecting fish, honu and all the saltwater living life forms.

Healthy forests funnel rainwater down into the ground enhancing our water sources. 

There are so many benefits. 

To follow the Miyawaki method you get rid of grass and weeds and plant climax species really close together like how they occur in nature. 

(Koa and `Ohi`a lehua trees are two Climax species that we do now know how to nurture and grow)

Soil preparation is key. Get rid of weeds and grass and mix in compost. Lots of compost and organic matter gets incorporated into the original soil. Drainage is also very important. 

Adding mycorrhizae or native soil from a healthy forest area might be advisable.

Soil tests help determine what soil type and fertility you have. 

After all this planning and preparation, the fun begins: Planting the forest.

The plant mix is trees, shrubs, ferns and ground covers, throw in some vines. A different plant mix would be suitable for various soil types, rainfall amounts and elevation. We have so many microclimates and soil types in Hawai`i.

Elevation is a very important consideration for growing native Hawaiian plants.   

For example, Koa seeds collected at 5000 feet on the richly soiled flanks of Mauna loa, would probably not thrive in Kapi’olani park.   It is partly soil (they do not like sandy salty soil), but even more it’s elevation. Cool night temperatures and other factors 

Often lowland plants can grow at higher elevations, but high elevation plants struggle and lower, hotter elevations. 

For the first few years you tend the forest, watering, and weeding. The book says you do this for three years. Maybe in Hawaii we need to tend to it longer with watering and weeding and adding to the mulch beds.

Then it can basically care for itself but it’s still good to do some nurturing. 

That is what horticulture is: Close monitoring, observation, and careful tending of your plants.

Like in a natural forest, leave the leaves. They nurture the soil.

Rachel admires koa tree

ASHS coming to Honolulu!

By Heidi Bornhorst 

Heidi Bornhorst Keynote Speaker

A prestigious Horticulture group is coming to Hawaii for a weeklong conference.

The American Society for Horticulture Science will be here on Oahu for a week long conference beginning Monday September 23, 2024, closing on Friday September 27.

Over one thousand attendees are signed up and registration is still open. (1067) at last count.

This is great for Hawaii gardeners, Horticulturists, Botanists, and plant scientists.

The conference will be held at the Hilton HawaiianVillage hotel, right on the beach in beautiful Waikiki.

Renowned for its extensive gardens, featuring many native Hawaiian plants, along with canoe plants and tropical exotics, it is a great venue for these plant loving scientists to enjoy.

The Hilton is also right next to the Hale Koa Hotel (where I served for over 10 years as Landscape Director).

The extensive landscaped grounds of the Hale Koa were designed as a botanical garden and the plantings there are very impressive and worth a stroll.

There are many wonderful gardens in Waikiki, amidst all of the hotels and high-rises.

I was very honored to be invited to be the keynote speaker for this conference and I plan to be talking about my favorite: Growing native Hawaiian plants.

There are over one thousand native Hawaiian plant species, and we now are growing about 100 of these Hawaiian plant species. We can grow more!

We have 1367 native Hawaiian plant species. Over 90% of them are endemic, meaning they only grow naturally here in Hawaii. About 9% of them are extinct, and many are rare and endangered.

Some are common and easy to grow, and we see them all around. Examples are: Hala, beach naupaka, `ilima, Hapu`u or Hawaiian tree ferns, and Kou and Milo trees.

Other native plants are less common in our gardens and landscape, but horticulturists are working to change that.

​My friend, Dr. Mike Opgenorth, who is the Director of Kahanu Botanic Garden in Hana, Maui will be speaking on Thursday about his PhD work on our endangered native Hawaiian Gardenias 

Many more students and graduate student at the U.H. are studying how to grow and perpetuate native Hawaiian plants.

The landscape or “Green industry” here in Hawaii is doing the groundwork with native plants.

Home gardens now feature native Hawaiian plants especially those loved by lei makers such as `Ohi`a lehua, `ilima, Palapalai and Pala`a ferns, and our native fragrant Hawaiian white Hibiscus, Koki`o ke`o ke`o.

Our public parks and urban forests are growing more native plants too.

Let’s learn and grow more, let’s perpetuate our native Hawaiian plants together.

https://ashs.org/page/ASHSAnnualConference

Variegated Hala tree. Pandanus. Growing happily at the Hale Koa hotel.

Silver Buttonwood trees – Horticultural Legacy at our Botanical gardensHawaii

 

Q: What are those gorgeous silvery street and park trees?  Some are at Sandys Beach, some Giant ones are on Pa`alea street in Palolo Valley, and some are at Ala Moana beach park.  Please inform us about these

Mahalo, M. Silva, Palolo

A: Silver buttonwood trees! AKA Sea Mulberry, or Button Mangrove.  Conocarpus erecta is the Latin name.  they grow naturally in mangrove swamps and are in the Combretaceae plant family, they have a very interesting horticultural history that I am happy to share.

As you may know they are very wind resistant, xeric (drought tolerant) and salt tolerant.  The bark and gnarly trunks are very attractive, especially as the trees mature.  You can make lovely lei with them.  Keiki can make a fun lei using masking tape and the leaves – easy and gorgeous!

 

HB- silver bttnwd tree -landscape

Silver Buttonwood amidst Carissa, Rosemary and Wax Ficus

 

At Lei Day in Kapiolani Park this year (and a HUGE mahalo to all the dedicated City of Honolulu, Parks and Recreation and Honolulu Botanical Garden Employees and Volunteers, who organized and coordinated that major public, free event in our park) we saw some fab lei, using various parts of silver button wood trees.  Some used the fruit clusters, some used the leaves, some crafted the leaves into silver “rose” buds and so on.

Our late mentor Paul Weissich had just become Director of the Honolulu Botanical Gardens (HBG) in 1957.  He was reviewing all of the interesting plants growing in the nursery and lath houses at Foster Botanical garden (FBG).

Weissich found a flat of seedlings.  Some were green and some were silvery.  One keiki was super silvery.

 

HB-silver buttonwood tree

Silver Buttonwood tree in a salt Drenched, Hot, Dry Diamond Head, coastal Garden; See How it “Lights UP” the landscape?

 

He selected the silveriest of the silvers and had them potted up into larger individual pots. The best, consistently silver one was selected and more were propagated from air layers. He watched over them and had the expert plant propagators nurture and grow them up. This is a prime example of ‘Horticultural selection’.

He planted a bunch of them at Ala Moana beach park, which was an adjunct Botanic garden back in those days (and still has his legacy of tough, salt tolerant interesting, rare and unusual trees growing).

A mixed silver and green hedge of them is still growing today around the tennis courts at McCoy pavilion.

One of the silveriest was planted at Foster Garden and its gnarly and sprawly and has a growth habit something like an ancient time gnarled Olive tree.  We have been talking about making this an Exceptional Tree.

Over the years more of the silvery trees were grown and planted in beach parks like Sandys and as shady tough street trees in Oahu neighborhoods. They make a tough specimen tree (especially nice when up lit with solar lights for your “Moon Light Garden”), a good hedge or windbreak.

Button woods are native to a broad area from the Bahamas, to the Caribbean coastal tropics and all the way to West tropical Africa.

This is one of the many Horticultural legacies of Paul Weissich who passed away this year at age 93.  He really grew our beautiful and amazing botanic gardens here on Oahu. His legacy is our five Honolulu Botanical Gardens: Foster Lili’uokalani, Wahiawa, Koko Crater and Ho`omaluhia, as well as people like me and my Husband Clark whose career and lives he nurtured, just like that flat of keiki silver buttonwood trees all those years ago!

 

HB-silver buttonwoord lei

Epic Silver themed Kupuna lei featuring Fruits of silver Buttonwood, Delicate Baby’s Breath, Hinahina and silver leaf.