Sites:
H=Horticulture Research Center, So. Burlington, USDA zone 4b
Spring 2007 bulbs | Perennial trials listing
photos: summer 1997 | 5/12/00 | 5/19/00 | 5/28/00 | 6/3/00 | 6/20/00
U=UVM greenhouses [view, 47K], Burlington, including outdoor student garden test beds, USDA zone 5b
photos: freezing research 1997
M= Perry's Perennials, Milton, USDA zone 4a
Winter soil temperatures, Summer Soil Moisture, Sunflower trials 2000 | 2002
W=Waterfront Park, Burlington, USDA zone 5b

Current | Past Studies

Powdery mildew studies (U):
New cultivars (15) of beebalm were established in 1998 (H) for evaluation for genetic resistance to powdery mildew in a randomized complete block design. Plants were evaluated for drought, weed and cold stress early 2000, then potted for subsequent mildew studies at the UVM greenhouse (U). Due to poor growth in pots, plants were put into field studies in Milton in 2003. Plants will be dug, divided, and potted this year for continued trials in pots.

During 2000 and 2001, 5 organic controls were tested on Snow White bee balm (see article below) in containers (U). In 2003 a study with Phlox pan. Mt Fuji was established to look at the effect of salt and milk solutions on mildew, as have proved effective on grapes and vegetable crops.

Beginning in 2003, 24 new cultivars of garden phlox will be compared in a randomized complete block design for resistance to powdery mildew in field studies in Milton. (8/03 photo). No results were obtained this first year, due to poor mildew pressure, with the study to be repeated in 2004.
[Slide Show on past studies of powdery mildew on phlox and monarda.]
1998 Scientific article on powdery mildew among bee balm cultivars
1999 Scientific article on organic powdery mildew controls on phlox
2000 Scientific article on organic powdery mildew controls on bee balm
Article on Bee Balm cultivar stress results
Powdery Mildew on Phlox and Monarda leaflet(new 12/01)
Powdery Mildew Controls on Phlox and Monarda leaflet (new 12/01)

New England Aster cultivar rust resistance (U):
About 15 cultivars of Aster novae-angliae were established for evaluation for genetic resistance to rust in a randomized complete block design in the field.  After two years of defoliation due to lacebugs, plants were potted and moved to the UVM greenhouse.  With poor growth in pots, plants of the 12 cultivars were subsequently planted in randomized complete block field studies in Milton in 2003 with data obtained late in the a season (2003 rust article).  Data were not available since due to  minimal rust.  

In 2006-2007 hardiness studies (with assistance of new grad student Sarah Kingsley Richards) will look at:

• effect of  soil moisture on 3 cultivars of sedge (Carex)
• effect of plant age (fall potted, year old, 4-inch pots) on winter survival, 3 cultivars
• hardiness in pots of select Steppables (low groundcovers)

Shrub rose evaluation (H,M):
Over 5 dozen cultivars of shrub roses (list and characters), emphasizing new series such as the Parkland, Meidiland, Explorer and David Austin ones, are being evaluated among these sites and in cooperation with the University of Maine (Dr. Lois Stack) for hardiness, performance and disease resistance (rose ratings (updated 9.05)  article on top 15 rated to date).
photos: June 2003, north side | June 2003, inside

Lilac Evaluation (M):
Okay, they're not herbaceous perennials, but are effective in our climate used in combination with them, and a key shrub in Vermont.  This evaluation over many years of over 230 varieties emphasizes bloom and disease resistance, with many photos and a table of blight resistance observations.

Past Studies

Effect of soil moisture on hardiness
monitoring field soil moisture, and the effect on freezing of wet or dry watering regimes (below 10% and above 20% soil moisture content) on 3 cultivars (funding by the NH Horticulture Endowment); first year summary, first year photo Astilbe dry, Astilbe wet (second year results forthcoming)

Overwintering Covers
New overwintering fleece cover in various layers on 20 cultivars, including a sandwich of straw between white poly layers, and one or two layers of fleece (thick felt material) with and without a white poly covering (funding by New England Greenhouse Conference; plant donations courtesy of Creek Hill Nursery, PA), compared with same cultivars under controlled freezing. Performed 2003--04, 2004-05.  Results forthcoming.
Photos: before covering fall 2003 | after covering 2003 | before 2004 | after 2004 | close-up 2004

Media and fertility
Three cultivars (Hemerocallis Stella d'Oro, Geranium 'Max Frei', Dianthus 'Arctic Fire') were potted in 12 combinations of media and fertility to observe effects on growth after one season.  Media include commercial peat-lite, local organic, and German peat-lite products.  Fertility include organic liquid, standard liquid, and new color-coded Osmocote products.
Fertility and media 2003 results | Fertility and media 2004 results

Ornamental grass hardiness (H,M, U)--1999 data:
At 3 sites in the Champlain Valley (USDA zones 4a, 4b and 5b), at least 2 dozen cultivars of ornamental grasses were evaluated over a five year period for winter hardiness, as well as other landscape features. Many are recent introductions to the U.S. from Germany including new ones this year. Results were included with those from an extensive collaborative national effort.