Garden Talk: August 16, 2007
From NGA Editors
New Color for Late Summer-Blooming Lobelia
Lobelia speciosa is a great late-summer blooming perennial that?s easy to maintain and brightly colored. The ?Fan? series is a new hybrid line that was created from a cross between Lobelia cardinalis, L. syphilitica, and L. fungens. Selections in the Fan series feature 2-foot-tall plants with larger and earlier blooms than Lobelia cardinalis. There are selections with flower colors of rose, burgundy, and blue, and now a new variety in the line not only features a novel color, but unusual colored flower stalks as well.
Lobelia ?Fan Salmon? has deep pink-salmon blooms surrounding a rich burgundy colored stalk. Like all the Fan series, ?Fan Salmon? flowers until frost and adds a rich color to fall gardens, especially when paired with other late-blooming perennials like asters and sedums.
The Fan lobelias will reflower if old flower stalks are cut back. They grow best in moist soils and are striking when planted along a pond, in a wet area, or even in a container. They are hardy in USDA zones 6 to 10, so gardeners in colder areas should protect plants in winter or treat them as annuals.
For more information on the latest variety in the Fan series, go to: Burpee Seed Company.
New Dwarf, Weeping Dawn Redwood
Dawn redwood is a fast-growing, feathery-leaved specimen tree that resembles the coastal redwoods of California but is deciduous and more widely adapted. This striking tree looks beautiful standing on its own in the yard or grouped together in a small grove. However, it?s not a very practical choice for small yards since it can reach more than 50 feet tall at maturity.
For gardeners who like the soft look of this majestic tree but don?t have space for it, now there is a diminutive version -- ?Miss Grace?. Metasequoia glyptostroboides 'Miss Grace' has soft, feathery, textured leaves on branches with a weeping habit. The needles have a blue cast that turns a colorful orange-brown in fall. ?Miss Grace? is slow growing. The ultimate height of the tree is rarely more than 10 feet tall.
For more information on ?Miss Grace? dawn redwood, go to: Wayside Gardens.
Eat Broccoli and Cauliflower for Prostate Health
We know that eating a wide range of fruits and vegetables is good for your health. In particular the crucifer vegetables -- broccoli, cauliflower, cabbage, Brussels sprouts, and turnip greens -- have been suggested to help prevent diseases such as heart disease and colon cancer. Now, prostate cancer can be added to the list.
Researchers from the U.S. National Cancer Institute and Cancer Care Ontario in Toronto studied more than 29,000 healthy U.S. men aged 55 to 74 for an average of four years. During the study 1,338 were diagnosed with prostate cancer and 520 with aggressive prostate cancer. The men who reported eating cauliflower more than once per week were 52 percent less likely to be diagnosed with aggressive prostate cancer than men who reported eating cauliflower less than once a month. Men who reported eating broccoli more than once per week were 45 percent less likely to be diagnosed with aggressive prostate cancer than men who reported eating broccoli less than once a month.
Even though researchers can?t guarantee eating crucifer vegetables will prevent aggressive prostate cancer, they do know that crucifers contain compounds that protect the DNA of cells and are beneficial to our overall health.
For more information on this research, go to: Web MD.
Kaolin Clay Can Increase Aphid Populations
Kaolin clay is an organic pesticide often sprayed on trees, vines, and vegetables to prevent many insects and diseases, such as aphids, mites, leafhoppers, leaf rollers, thrips, apple maggots, cucumber beetles, and powdery mildew. The clay provides a protective layer on the leaves and fruits that irritates these pests and prevents them from reaching the leaf tissue. It is often used as an organic alternative to conventional pesticides.
Even though kaolin clay has a good track record when used on many crops, there are exceptions to the rule. USDA researchers in Texas sprayed kaolin clay particle film on cotton plants to control aphids. The results were the exact opposite of what was expected. Aphid populations actually increased after kaolin clay applications.
Researchers suggested the aphids might have been attracted to the lower temperatures associated with the kaolin-coated cotton leaves when compared to the untreated leaves. This research illustrates the need to test any spray for possible side effects before widespread use.
For more information on this kaolin clay research, go to: Entomologia Experimentalis et Applicata .