It’s always exciting to discover new plants or improved selections of familiar favorites. Even the most dedicated gardeners have a hard time keeping up with the plethora of new varieties that appear on the scene almost daily. With this in mind I made a trip a few weeks ago with two gardening friends, Anne and David to the Trial Gardens at the University of Georgia. http://ugatrial.hort.edu Once we found the gardens, tucked in behind some greenhouses and next to the pathology building we were glad we had made the trip. Free and open year-round to the public, the trial gardens are a great way to observe up close and personal a large selection of annuals from all over the world. Plants are evaluated for their flowers, leaf color, habit, resistance to insects and diseases and overall appearance. They also evaluate perennials at the gardens but I will focus here on annuals that made us take note. We visited the gardens and made our top choices before referring to the UGA website to see how they rated the same plants. I was not surprised that our favorites rated well under their system too.
Finding good doers for our hot, humid summers is not always easy. Popular annuals that I have known, grown and enjoyed over the years include the narrow-leaf zinnia, Zinnia angustifolia with orange flowers and the hybrids including ‘Profusion White.’ This zinnia only grows 12 to 18 inches high but pacts a punch with its nonstop flowers making it perfect to fill in gaps in the perennial border or to enhance a container planting. New to me is Zinnia ‘Profusion Yellow’ and two plants from the Zahara series, ‘Zahara Fire’ and ‘Zahara Double Orange.’ The brilliant flowers look great are bigger than the species. These three selections were all growing next to each other and it was hard to pick a favorite.
The annual purple fountain grass, Pennisetum setaceum ‘Rubrum’ and the various selections may not be new to most gardeners but there is a group of fountain grasses that elicited high praise both from me and my cohorts. Ornamental millet, Pennisetum glaucum ‘Jade Princess’ grows 3 to 4′ tall and forms a mound of lime-green leaves with striking dark maroon seed heads that don’t have pollen. For colorful foliage that stands up to our weather, Pennisetum ‘Princess’ and Pennisetum ‘Princess ‘Caroline’ offer choice alternatives to Phormiums, also known as New Zealand flax; and they are much more vigorous in our climate. P. ‘Princess’ boasts purple foliage that gets even darker with hotter weather, and P. ‘Caroline,’called ornamental Napier grass, also has brilliant purple foliage but only grows to 3′ tall; great news for southern gardeners. Whether you plant them in containers or in the ground these fountain grasses are bound to please; providing color and movement from spring until frost.
Also on trial, (that was fun to write) were numerous plants that all looked very much the same to me as the good doer, Euphorbia ‘Diamond Frost,’ which looks like baby’s breath but blooms all summer even with intense heat and, it will tolerate some drought too. Some selections may have been taller or shorter or had more blue-green foliage but the differences were not great. A large pot of the showy chartreuse green Boston fern, Nephrolepis exaltata ‘Rita’s Gold’ will brighten up any shade garden especially when combined with begonias, impatiens or caladiums.
One of the most unusual annuals that was new to the three of us is Ptilotus exaltus ‘Joey’ an Australian native that grows to about 1′ tall with feathery spikes of lavender and white and thick foliage, it seems to hold up well in hot, dry weather.
Of the perennials on display two unusual selections I liked were Vernonia lettermanii ‘Iron Butterfly,’ a compact selection of ironweed with small purple flowers and delicate foliage similar to that of Amsonia hubrichtii; and the cup plant, Silphium perfoliatum, which is blooming in my garden now.
Botanical name: Silphium perfoliatum
About the plant: This perennial grows 6 to 8′ tall or taller. In late summer it produces masses of yellow daisy type flowers. The stout leaves encircle the stem and form a cup that holds water which attracts birds.
Use in the garden: Great at the back of the border for late summer bloom.
Planting and Care: Full sun and a moist well-drained soil is ideal but this native will also tolerate dry soil.
Source: Woodlanders, Inc., 1128 Colleton Ave., Aiken, SC 29801, 803-648-7522