Cup of gold is one of those old-fashioned Hawai'i garden plants that we don't see around much these days. It is big. I mean really big.

It is what plant scientists call a woody liana — a big old tropical vine that gets woody and wild with time. It wants to crawl and sprawl all over massive trees until it can stick its big blooming heads up into the sunlight and display some brilliant blooms.

One place where you can see it is in Kaua'i's Allerton Garden, an integral and valuable part of the National Tropical Botanical Garden. There the wild, woody, tropical American escapee has the proper amount of room to sprawl — it rambles wildly up into the pink shower trees, banyans and other trees.

You can see the blooms if you walk on the old moss-rock walls and along the old train tracks. The other view is down in the garden amidst the classic water features. The cup-of-gold blossoms are reflected in the still and running water gardens and the old flowers drop off, adorning the grounds.

Closer to home, you can find this garden gem along the Old Pali Road. Take a nice country drive and look for the gold.

Some people say this is a noxious weed, but it does not set seed in Hawai'i and does not seem to invade our forests on its own.

Once planted by people, it truly grows big and heavy, so think about it before making the commitment. Make sure you have a big, strong tree, or better yet a specially designed stout, solid trellis for the vine to grow on and display its beauty in your pau-hana, evening-splendor garden.

As keiki — in the days before time-lapse photography was common — we would pick a big cup-of-gold bud that was destined to open that night. We'd put it in a vase of water on the dinner table under a light and watch — and listen — for what happens: The bud pops in a mini explosion of floral amazement, and starts to peel back and open right before your wondering eyes. (This is a good test of patience and observing and appreciating the natural world, for modern-day TiVo-overexposed, teched-out kids).

The flower is a perfect light gold with an interesting, singular perfume in the evening. The flower will last for about a day in water.

On the plant, the flower will fall to the ground the next day. On a big, healthy plant you will see more buds that will bloom and do their amazing thing in the days to come.

Scientists call cup of gold Solandra hartwegii, and it is in the Solanaceae plant family along with tomatoes, potatoes, eggplant, ornamentals such as angels trumpet, and native Hawaiian plants such as the rare coastal 'ohelo kai, and the medicinal popolo.

Heidi Bornhorst is a sustainable-landscape consultant. Submit questions to islandlife@honoluluadvertiser.com or Island Life, The Advertiser, P.O. Box 3110, Honolulu, HI 96802. Letters may be published or distributed in print, electronic or other forms.