Garden Talk: October 23, 2008
From NGA Editors
New Tri-Colored Japanese Maple
Fall is for tree planting. The warm soils and cool, rainy days create perfect conditions for tree roots to grow before the cold days of winter. Japanese maple is a favorite specimen tree of many gardeners, and now comes a new selection that features tri-colored leaves.
'Gwen's Rose Delight' Japanese maple (Acer palmatum 'Shirazz') grows 15 to 20 feet tall and 10 feet wide at maturity with a weeping habit. The heat-resistant, deeply cut foliage unfurls in spring, featuring crimson-pink leaves and white margins. The color holds well in summer. In fall the leaves turn a brilliant crimson. 'Gwen's Rose Delight' grows best in full sun on well drained soil and is hardy in USDA zones 5 to 9.
For more information on this new Japanese maple variety, go to: Willoway Nursery.
Instant Compost Tea
Gardeners know the benefits compost tea can have on their gardens. Not only is it a quick and efficient way to deliver nutrients to plants, compost tea also feeds the microbial life in the soil. It also has been touted as a way to prevent diseases when used as a foliar spray. Although making your own compost tea is easy, sometimes it's simpler to reach for a bottle.
Now there is a pre-made compost tea available in bottles. Bio-Balance is made from a variety of manure sources. It's organically produced, loaded with microorganisms to stimulate biological soil life, and contains no human pathogens. It's claimed to also be odor-free, making it useful indoors in greenhouses and on houseplants, without causing an offensive odor.
For more information on this instant compost tea, go to: The Compost Tea Company .
Trials of the Best Organic Weed Killers
Organic gardeners often struggle to control annual weeds in their gardens. While there are many organic products on the market touted as helpful in controlling weeds, there has been little research testing them against each other.
Researchers at the Organic Farming Research Foundation and Purdue University tested four different organic weed control sprays, plus flaming with a hand-held flamer, on seedbeds to be planted in greens. Weeding greens and lettuce beds can be very time consuming, especially for organic growers, so finding an effective alternative to reduce weeds will save growers time and money. Researchers tested Burnout II (contains acetic acid), Matran 5 (contains clove and other essential oils), 10% vinegar solution, 13% vinegar solution, and an LP gas hand-held flamer. They were particularly focused on controlling chickweed, purslane, galinsoga, and grasses. Seedbeds were tilled and allowed to sit for 2 weeks so the weeds could germinate. Three applications of each treatment were made on the 3' by 5' test beds in May, June, and August.
It turns out organic sprays weren't the best solution. Although Burnout II reduced the weeding time the most overall, the hand-held flamer was more convenient to use and more effective in controlling tougher weeds, such as grasses and purslane. Matran 5 was the next most effective weed killer. All treatments worked best if the weeds were treated when less than 4 inches tall.
For more information on this research, go to: Organic Farming Research Foundation.
Blue Flag Iris Filters Pesticides
Our native blue flag iris (Iris versicolor) is a beautiful perennial that grows well on lakeshores, swamps, wet meadows and along stream beds. Now it appears this iris can be effective in controlling pollution as well. Researchers at the USDA and University of Massachusetts grew 10 different water-loving plants in a greenhouse setting. Over a three-month period, they measured how much of four common pesticides were absorbed by each.
The top performers were blue flag iris, eastern gamma grass, and big blue stem. Blue flag iris also had the added benefit of being an attractive ornamental. If you are concerned about pesticides running into your property from your neighbor's yard, local farm, or golf course, consider planting a vegetative filter strip of this iris to help keep your groundwater clean.
For more information on this research, go to: Journal of Environmental Quality. Photo courtesy of the USDA.