Tropical Gardening: If no room to plant trees then plant on trees

  • Photo courtesy of Voltaire Moise A pile of rocks recently left after land clearing was instantly landscaped with colorful bromeliads by Kyle McWhirter of Kaloko mauka. Can you spot the family Jack Russell terrier exploring the bromeliad bed for geckos?

As the days get shorter, mainland folks like to brighten up their home with bouquets of colorful cut flowers, but for most kamaaina, flowering plants are another option. Instead of lasting a few days, many flowering plants can last for years. If you like interior or exterior gardening the easy way, then you might consider a group of easy care plants referred to as air plants. If you are like me and have no more room in the garden to plant trees you may consider using the trees to expand your gardening talents by creating air gardens.

Many in this group require no soil and may even be grown on rocks. Technically, plants growing on rocks are referred to as lithophytes. When you think of it, much of the vegetation growing on our young lava lands fits in this category.


This group of unusual tropicals referred to as epiphytes and lithophytes use their roots to attach. The little nutrients and moisture they require are supplied by debris and precipitation they capture. The group includes many ferns, orchids, bromeliads and even some cacti. Although epiphytes grow attached to shrubs and trees, they are not parasites, since they do not take their nutrients from the plants on which they grow. Air plants have some of the most beautiful flowers and unique foliage in the plant kingdom. They generally require less care than most other ornamentals. Many folks think air plants are difficult to grow but this is not the case. Our tropical climate is ideal for air plants that are virtually impossible to grow outdoors anywhere else in the United States except in the warmest parts of California and Florida. Here, many grow with almost no care.

Orchids and bromeliads are probably the most well known of the epiphytes. Many species have been introduced. Local nurseries have them available in abundance. If you have a tree or lanai in which to hang pots, you can have flowers the year round. All it takes is a little common sense, water and fertilizer. In fact over watering or over fertilizing is the most common cause of their demise. When buying orchids and bromeliads, it is important to get healthy plants. Ask the grower or nurserymen about the particular species and its care. When grown in containers, they will require repotting every 2 or 3 years. To avoid the problem of repotting, many gardeners remove the plants from the pot and attach them to the branches of a tree. Rough barked trees like paperbark, monkeypod, calabash and African tulip are usually best.

The epiphytic ferns and cacti may be also grown in pots or on trees. The secret of success is to be sure they have good drainage. Fertilize lightly every 2 to 3 months to keep plants in active growth. But if plants are attached to trees, this is not required. Several brands of orchid fertilizer are available. They are satisfactory for other air plants as well. These are specially formulated and when used according to directions will give excellent results. Disease and insect problems are few. If they do occur, our local garden supply dealers have fungicides and insecticides to quickly control the situation.

Give the air plants a try in your garden. Start with easy types such as bromeliads, like Tillandias, Billbergias, and Aechmeas. Staghorn and Resurrection Ferns are easy. Dendrobiums, Epidendrum and Oncidium orchids will thrive on a minimum of care. From there, move up to the more exotic Cattleya and Moth orchids. Local nurserymen can give you quite a few ideas on the types to grow and ways to grow them.

Bromeliads, cactus and succulents may do with very little water or fertilizer. Ferns and orchids should be watered every few days and fertilized about once a month.


Some folks worry that insects may breed in the center of bromeliads, especially mosquitos. These insects can be more than a nuisance since they may be vector for dengue fever and other diseases. That is why natural insect control with lizards, amphibians and birds makes good gardening sense.

For further information, contact the UHCTAHR Master gardeners in Kona at 322-4893 or Hilo at 981-5199.

Leave a Reply

Your email address will not be published. Required fields are marked *


By participating in online discussions you acknowledge that you have agreed to the Star-Advertiser's TERMS OF SERVICE. An insightful discussion of ideas and viewpoints is encouraged, but comments must be civil and in good taste, with no personal attacks. If your comments are inappropriate, you may be banned from posting. To report comments that you believe do not follow our guidelines, email