Gardening with Galligan: Showcasing shrubs

If you want to enjoy a really nice, carefree combination of flowers, take a good look the next time you go into the library by the side door.

That very attractive yellow-flowered shrub, in full bloom last week, is hypericum. The purple flowering plants, one of the later blooming varieties, is perennial salvia. I never think of salvia as particularly attractive, but it looks terrific here and contrasts so nicely with the bright yellow. I always grow a few myself and recommend the practice because they make excellent cut flowers, especially with peonies and roses.

It’s very often contrast, rather than anything else, that makes either a bed or a vase of flowers a delight to the eyes.

Hypericum, also known as St. John’s wort, varies in height from ground-hugging varieties to small trees, with large, showy flowers in shades of yellow and gold. This plant has been around for a long time and a number of its cultivators have won the Royal Horticultural Society’s Award of Garden Merit. Other varieties, however, have posed significant difficulties for farmers, where they have spread widely as soil-depleting weeds, and have also caused disease in livestock. A particular beetle, with a very long and Latin name, Chrysolina quadrigemina, finds most hypericums delicious and the beetles have been purchased for bio-control in areas where the plant has become invasive. St. John’s wort is on the composite list of Federal and State Noxious Weeds.

Many varieties of hypericum have a long history of use in herbalism. Their pharmacology is not well understood, but the plant does seem to have anti-depressant properties. When prescribed as psychiatric medication, it is usually taken in pill form or made into tea. There is research data available that does support significant effectiveness in the treatment of light and medium depression, but little impact on severe depression or obsessive compulsive disorders. It is also thought to heal wounds, suggesting the presence of antibiotic properties as well.

For landscaping purposes, hypericums are a good choice, since there are species for almost every climate. Although most noteworthy for their flowers, certain species have attractive fall color and fruit. The plants require well-drained soil; the amount of sun varies according to species.

Let’s move on to another shrub, equally if not more attractive, lagerstroemia, commonly known as either loosestrife or crape myrtle and yes, there are alternate spellings; crepe myrtle is equally acceptable. The plant was named for the Swedish merchant, Magnus von Lagerstrom, who traveled the world collecting plants and providing them to Carl Linnaeus, often called the Father of Taxonomy. His system for naming, ranking and classifying plant organisms is still in wide use today (with many changes). His ideas on classification have influenced generations of biologists during and after his lifetime. Native to the Indian subcontinent, northern Australia and the islands of the Pacific Ocean, crape myrtles like warm temperatures and high humidity. Welcome to Shelter Island!

The flowers of this shrub are wonderfully colored and include the bright red Dynamite Crape Myrtle, the deep Pink Velour Crape and the purple Twilight Crape Myrtle, which also has a bark that changes colors. The shrubs are from 3 to 5 feet tall, and bloom occurs, depending on the species, anywhere from July to September. It’s not a fussy plant and will grow well in full sun and well-drained soil with good air circulation. Partial sun will result in less than full bloom, not the ideal situation for full flowering.

Future column of the week: Speaking of Lagerstrom and Linnaeus reminds me that some time ago, last year or perhaps the year before, I had in mind to write a few columns on some of the famous “plantsmen” as they were called in bygone centuries. They were an intrepid group, traveling the globe when traveling was difficult and dangerous, risking their lives in adventures that brought pleasure to us all. I’ll try to get back to that before the summer’s gone, or perhaps wait until fall when there’s nothing really in bloom to talk about. Gardeners should know their own history!