Kauai - Botanical paradise?

A recent travel news article called Kauai, one of the Hawaiian Islands, a botanical paradise, and then talked about the all the remarkable plants: crotons, bougainvilleas, plumerias, philodendrons, mango, guava (!), poinsettia, hibiscus, and so on. No question that such plants grow well, even luxuriously in the wet tropical climate of Kauai, but like most visitors to this island, the travel writer had not seen one single native plant. The plants they noticed are what the Phactor calls "UTF", ubiquitous tropical flora, widely planted ornamentals. There are two factors at work here. One, people always bring plants with them from where ever they come, and this started with the Polynesians and has continued to this day. Two, plants and animals native to islands are often unable to deal with vigorous invaders having evolved in a place with few natural enemies. And like lots of immigrant organisms, organisms brought to islands become invasive in new habitats devoid of their natural enemies. So you have to look hard and walk some distances to find any native plants on Kauai. But you will see guava every where, a very easy plant to recognize with its smooth cinnamon-colored bark, and when guava arrived, whenever that was, but guava is a terribly invasive plant in Kauai. Invasions of immigrants take a terrible toll on native species. So while a pretty place, quite lovely in fact, and well worth visiting sometime, Kauai is more of a botanical disaster zone than a botanical paradise.

Gardening Mistakes

Everyone makes gardening mistakes. A couple of years ago the Phactor planted a plume poppy (Macleaya cordata) in what is by no means a small perennial bed (~30’ x 80’) and it only took two years to realize that this was the biggest, most impressive, most attractive, most aggressively invasive weed I ever purposefully planted. And every tiny piece of root could (and DID) give rise to a new shoot. You almost could not dig fast enough to keep in front of it. Be warned people! Sentence: death.

This past weekend was spent correcting another couple of gardening mistakes, just none as scary as a plume poppy. Ural false spiraea Sorbaria sorbifolia is actually a nice looking, very hardy, non-fussy, summer-flowering shrub, but again you had better have a large place for it. Once it gets going it spreads quite vigorously by means of shallow rhizomes. It filled a 10’ diameter area in a border garden in 3 years. Fortunately it’s shallow rooted and fairly easy to move or remove. Plant parole has been granted and it gets a 2nd chance in a slightly shadier, slightly wilder and bigger place.

The Phactor has not been a great success over the years with flowering vines. A non-flowering wisteria was adding injury to insult by pulling down the arbor especially built for it, concrete anchors and all. Of course, the removal might have been a tad premature because the vine had latched onto the burr oak beyond, and in the long run may have acted as a counter force pulling the other direction to stabilize the arbor. Unless of course the oak was pulled down too. Ah, the power of plants is something to behold. Sentence: death. The search will continue for a kinder, gentler flowering vine.

The jury is still out on a fancy staghorn sumac as it encroaches on bottle brush buckeyes and the rest of the world. Wonder when the neighbors will notice they have a new hedgerow plant?

Let the Phactor know about plants to look out for. Better forewarned than sorry.