Garden Talk: February 16, 2006
From NGA Editors
There are literally hundreds of rose varieties available for gardeners to plant. In order to help us choose the best ones, the All-America Rose Selections organization tests new varieties for two years in trial gardens across the country. The roses are evaluated by professional rosarians on a variety of factors, such as growth habit, flower production, flower color, fragrance, and disease resistance. Winning varieties receive the prestigious AARS award.
For 2006, four new roses made the grade. Julia Child rose is as warm and spicy as her namesake. This disease-resistant floribunda bush produces a yellow bloom with an antique flower shape and licorice candy scent.
Rainbow Sorbet is a multi-colored yellow rose with pink edges. This upright-growing floribunda is winter hardy and exceptionally resistant to black spot disease.
Wild Blue Yonder is a uniquely colored shrub rose featuring reddish purple, single flowers with a citrus scent.
The only hybrid tea rose in this years winners is Tahitian Sunset, with orange-yellow flower buds that open into 5-inch-diameter, apricot-pink, anise-scented flowers.
For more information on these AARS-winning roses, go to: All-America Rose Selections.
A Deer Control Roundup
Deer are a big problem for gardeners in many areas of the country. While there are a plethora of home and commercial remedies and deterrent methods available, it can be hard to differentiate between them and know the best overall strategy to use.
One group that has been researching deer damage on its property for more than 20 years is the Institute of Ecosystem Studies in Millbrook, New York. The institutes mission is to create and disseminate information on maintaining healthy ecosystems. Deer browsing is having a detrimental impact not only on gardens, but on forest ecosystems as well.
The Institute has been monitoring deer damage on almost 2000 acres to determine preferred plant species and the effectiveness of various home and commercial products and methods for deterring deer. They've found that deer change their diet seasonally, eating broadleaf evergreens (such as rhododendrons) and conifers in winter, but ignoring them in summer in favor of more succulent plants, such as hydrangeas, weigela, and mock orange.
They've found that scent-based repellents work best when used before browsing begins and when used in abundance to overwhelm an area with a scent. The most effective approach is to combine scent and taste deterrents, however if your area is experiencing a combination of drought, poor tree nut production, and high numbers of deer, you're likely to find deer damage no matter what you do.
For information on controlling deer damage, types of fences to use, and perennial and woody landscape plants least likely to be browsed by deer, go to: Institute of Ecosystem Studies.
A Better Solution for Powdery Mildew
For a number of years baking soda (sodium bicarbonate) sprays have been recommended for controlling powdery mildew and black spot fungal diseases on roses, phlox, and other garden plants. Baking soda has been shown to not only prevent fungal spores from getting established, but also to kill them once they get started. But baking soda sprays don't readily cover the leaves, and they quickly wash away. The addition of horticultural oil improves the coverage but can damage foliage.
Now a new product provides an alternative to the common baking soda solution. GreenCure is a mixture of potassium bicarbonate and a spreader-sticker, and it's 25 to 35 percent more effective at controlling fungal disease than straight baking soda. Its formulated to completely cover the leaf surface, yet not be harmful to the foliage. GreenCure has also proven to be as effective as chemical fungicides in controlling the disease, making it a safe alternative for both outdoor and indoor use.
For more information on this new fungicide, go to: GreenCure.
New Arabian Lilac
Lilacs (Syringa sp.) are popular ornamental shrubs in many northern gardens. The Arabian lilac (Vitex trifolium purpurea Fascination), while not a true lilac, is a good alternative for warm-weather gardeners and a colorful plant in any landscape. It features lilac-blue flower panicles on purple-colored foliage.
Fascination grows quickly into a shrub 6 to 8 feet tall and wide. Its foliage is a blushed purple on top and dark purple on the bottom. The flowers appear from new growth all summer. Although not fragrant, the shrub still gives a lilac-like appearance in the garden and is attractive even when its not flowering.
Fascination grows best in full sun. Since it's only hardy to USDA zone 9, its best grown as an annual or protected perennial in most areas of the country. It also looks great in containers or as an accent plant on a deck or patio.
For more information on this unique plant, go to: Hines Horticulture and look under New Products.