Botanical gardens have greatly improved our quality of life in Hawai'i, bringing wonderful plants and trees to our gardens, parks and streets, and passing on and expanding horticulture knowledge about our precious and rare Hawaiian plants.

At Foster Botanical Garden, you can find edibles like tamarind, mangosteen, chicle and akee apple; shade trees like Singapore plumerias, cigar box and kapok; and even the original false kamani or tropical almond. Waimea Arboretum and the National Tropical Botanical Garden are also pioneers in growing and perpetuating Hawai'i's native plants.

For the past 47 years, the Friends of the Honolulu Botanical Gardens have known when fall arrives because of the group's annual fall plant sale. It's the time for serious garden shopping and to plan your early garden gift shopping for Thanksgiving, Christmas and the holidays. Fall means the rains return, and it's the best time to plant trees, shrubs and bulbs.

This year, the fall sale will be on Oct. 4 from 9 a.m. to 2 p.m. at Foster Botanical Garden. It will feature a plant sale and garden fair with all kinds of old favorites like gingers and heliconia (new varieties continue to come in).

There will be bromeliads, cactus and succulents and native Hawaiian plants like koai'a, 'ohi'a lehua and na'u, or native gardenia. The sale will also have lotus and water lilies, and other water and bog plants like cattails.

For those who want to try something new, there will be some pine tree varieties that are adapted to our Hawaiian subtropical climate and water gardens that are fun and easy, whether done large or on a small apartment's lanai.

And there's more: For years, a tiny, yellow-flowered zinnia grew on a cinder block wall in a very hot corner of the nursery at the garden. It was so pretty and tough, a true survivor plant and so cute!

The Zinnia maritima will be offered at the event and is nice in a garden or pot and may have potential as a cut flower or an addition to haku lei. Grown by volunteers at the Ho'omaluhia Botanical Garden nursery, there are about 50 of them in 6-inch pots, according to master grower Paul Weissich, director emeritus of the Honolulu Botanical Gardens.

Under the leadership of horticulturist Alvin Tsuruda, the Friends group, the Oahu Nursery Growers Association and O'ahu's premier plant nurseries will be bringing one of the largest and most varied collections of plants for fall landscaping, including native plants and exotic hybrids. Bill Southwood will be bringing a new Selaginella fern.

The Hawaii Potter's Guild will also display a terrific selection of original, hand-crafted ceramics.

Wahiawa community leader and epic landscaper Grace Dixon, who is co-chairing the event with Tsuruda, shared some of her mana'o with me for this article, as did Weissich.

The educational component of the sale will include me, your local plant (student) guru and columnist, and Greg Koob as "plant doctors"; Kevin Eckert, a certified arborist, will talk about pruning and tree care; and Ted Radovich from the University of Hawai'i College of Tropical Agriculture will teach us everything we ever wanted to know about vermiculture.

In addition, educational displays on weeds and invasive plants will be set up by the O'ahu Invasive Species Committee, and a display on native Hawaiian plants will be presented by the Hawai'i Division of Forestry and Wildlife.

The event is free. If you want to volunteer or find out more, call Kathy at the Friends of Honolulu Botanical Gardens at 537-1708. The garden is at 50 N. Vineyard Blvd.

Even if a plant or two doesn't follow you home, a visit to this green original urban forest oasis near Downtown Honolulu is always a refreshing and enlightening experience. We all "own" the city's Foster Botanical Garden.

Mahalo to the benevolence and vision of Mrs. Mary Mikihala Robinson Foster.