If you want to try growing orchids and rub elbows with the experts, be sure to check out the Hilo Orchid Show and Sale this coming Friday, Saturday and Sunday, July 29-31. According to Richard Kelley, this year’s theme is Orchid Ohana. The show is returning to the Edith Kanaka‘ole Stadium after 2 years of a COVID pandemic induced break. Show chairperson and president Karl Mendonca points out that there will 10 of Hawaii’s top orchid hybridizers/nurseries with a huge variety of plants on display and available for sale. The show will present demonstrations to help beginners on the care of different types so their new purchases will thrive for many years. There is a nominal entrance fee and keiki get in for free.
There are many orchid species and hybrids that are easy to grow in Hawaii. Orchids are well adapted here and many species need almost no care. In fact, several orchids have naturalized and can be found growing in abundance. These include the Bamboo Orchids, or Arundina, from the East Indies. This orchid is common in open, grassy areas of the East Hawaii. The Phaius or Chinese Ground Orchid is found in moist forested areas along with the Spathoglotis or Malayan Ground Orchid. The Spathoglotis comes in many colors from purple to yellow and orange. These may be found at many local nurseries.
For the more advanced gardener, try the Butterfly orchid or Phalaenopsis. It is desirable for corsage use. Lavender or white flowers are most common. Flowers will average about two inches across and will remain open for several weeks.
For high elevation gardeners, try the Cymbidiums. Cymbidium is an exciting genus with hybrids flowering in a wide range of colors including pink, red, yellow, green, maroon, bronze and white, in bold vibrant tones as well as more delicate pastels and art shades. Their tall, erect, arching, or hanging sprays, durability and longevity, ease of cultivation, and usefulness as a potted plant, landscape plant, or commercial cut flower have led to tremendous worldwide popularity. Conventional varieties require cool evening temperatures of about 55 degrees during the late fall and winter months for good flowering to take place. Such conditions occur naturally in Volcano, Kamuela and upper Kona on the Island of Hawaii. Some are adapted to lower elevations.
To grow most orchid species, here are some helpful hints. Most orchids require partial shade for best growth. A good rule to follow is to give the plants all the light they can stand without scorching. Excessive shade will result in lush, dark green foliage and few flowers. Too much light may produce scorched spots on the foliage. This means shade is needed immediately. Saran, lath or trees may be used for overhead shade.
Many Cattleya, Epidendrum, Oncidium and Vanda species will tolerate temperatures down to 45 degrees if in a sheltered location. But most orchids prefer minimum night temperatures of 55 – 60 degrees or more. In Hawaii, there really is no maximum temperature for orchids if the humidity and ventilation are increased in proportion to the rise in temperature. In general, temperatures that are comfortable for people also are agreeable for orchid plants.
Watering orchids must be adjusted to the need of each plant and the media in which it is grown. Many orchids can be grown in coarse cinder or even gravel. A large plant will require more water than a small one; orchids in large pots will dry out slowly compared to plants in small pots. Orchids in active growth will require more water than those in a semi-dormant state. This means that plants will require more frequent watering during the warm summer months than during the cool winter season. Over watering has been the main cause of death of orchid plants. Roots will rot, and the medium becomes soggy and soft, which is harmful to the plant. Remember to never water a wet plant under any circumstances.
Fertilization can be a controversial subject depending on species, media mix and location. Special orchid fertilizers are available. Follow the directions on the label. Some gardeners prefer to stay with organic sources. You can minimize orchid care by attaching orchids to a tree like Plumeria, Ohia, Monkeypod or Calabash, That way you can have dozens of blooming orchids even in a small garden.
Many more rare and interesting species will be available at next weekend’s orchid plant sale along with expert orchid enthusiast to answer your gardening questions. More information is available on the Hawaii Orchid Society website.