No abstract

In 2009, North Carolina State University researchers conducted a survey of residents from 13 North Carolina communities to gather information on attitudes and behaviors related to landscape water use. The survey gathered information on landscape type, water use, and the effectiveness of watering restrictions. Actual water‐use data for a two‐year period was anonymously matched with participating households. The survey achieved a 49% response rate. Most respondents indicated that more than 75% of their landscape consisted of lawn, with 60% using warm‐season turfgrass species. Those whose lawns were planted with cool‐season grass used more water than those whose lawns were planted with warm‐season species. A total of 42% of respondents restricted their landscape water use to new plantings or stressed plants. More than 88% of respondents watered by hand. In most communities, no watering restrictions were in place during this survey. Water purveyors can use the results of this survey to better understand their customers' outdoor water use and thus develop effective education programs on water conservation techniques related to landscape irrigation.

Landscape plant evaluations were conducted in eight states: Colorado, Minnesota, North Carolina, Ohio, Oregon, Pennsylvania, Texas, and Vermont for 17 switchgrass (Panicum virgatum) and five little bluestem (Schizachyrium scoparium) cultivars. Additional locations in Florida (Fort Lauderdale, Fort Pierce, Quincy, and Wimauma), Nebraska (Lincoln), and Lubbock and San Marcos completed 1 or 2 years of the trials. Plants were established in 2012 and data were collected for 3 years, 2013–15. Sites were asked to compile annual data on plant height, width, flowering time, fall color, pests, foliage color determined by the Royal Horticultural Society’s color chart, plant form, flowering date, floral impact, self-seeding, winter injury, landscape impact, and mortality. Texas A&M Agricultural Research and Extension Center (Overton), Florida (all four locations), and Vermont had the highest mortality rate. Southern Florida locations lost 50% of their plants by the end of 2014. Wide variation was reported for landscape impact, individual cultivar height, and width from different regions of the United States. Three of the 17 switchgrass cultivars, Cloud 9, Northwind, and Thundercloud, had a rating of 4.0 or higher averaged over six or more locations for plant form, floral, and landscape impact. ‘Shenandoah’ and ‘Warrior’ switchgrass had a rating of 4.0 or higher averaged over six or more locations for plant form and landscape impact, but not floral impact. Only one of the five little bluestem cultivars, Blue Heaven® rated 4.0 or higher, for plant form and landscape impact when averaged over six or more locations. This range of variability in landscape plant performance demonstrates the importance of local plant evaluations.

Sages (Salvia sp.) have long been popular as summer annuals, culinary herbs, and landscape perennials. We selected ‘Hot Lips’ hybrid sage [Salvia ×microphylla (Salvia greggii × S. microphylla)], a recently introduced perennial sage, to assess efficacy of the growth regulator flurprimidol for controlling height. Substrate drenches of flurprimidol at 0, 0.25, 0.50, 1.0, 2, and 4 mg per pot were applied using 240 mL of solution per pot on 17 June 2010. Plant height was recorded at treatment, 27 days after treatment (DAT), and 48 DAT. Flurprimidol drench concentrations of 0.25 mg per pot and higher controlled plant height by 20% to 41% 27 DAT and by 26% to 50% 48 DAT. While all treatments at 48 DAT produced a significantly shorter plant, concentrations between 0.25 to 1 mg would provide growers options for controlling plant growth by 26% to 44%. Using concentrations over 1.0 mg did not produce any additional control of height in hybrid sage.

Twenty-one cultivars of coneflower (Echinacea sp.) were evaluated from June 2008 to August 2010 in two locations in North Carolina. Plant size was measured once during each growing season. Evaluators rated overall plant quality, as well as flower and foliage aesthetics. Plants were rated on a scale from 1 to 4, with 1 = poor and 4 = excellent. Any disease and insect problems were noted. Over the two-year study, average mortality rate was 34%. Cultivars ‘Bravado’, Kim's Knee High®, ‘Pink Double Delight’, and ‘White Swan’, had consistently high ratings, while ‘Emily Saul’ and yellow coneflower (E. paradoxa) rated the lowest. Kim's Knee High®, ‘Pink Double Delight’, and ‘White Swan’ received some of the best scores for flower quality, whereas yellow coneflower and ‘Ruby Star’ rated the lowest. There were minor differences between the locations regarding plant size and ratings, particularly for yellow coneflower. Evaluators either favored or abhorred this plant. This may be due to reflexed ray flowers that mimic water stress. ‘Crazy Pink’ also had a similar petal presentation and rated about 2.0 for overall and flower quality. In 2009, after an exceptional bloom, many cultivars were infested with mites, causing aborted blooms and distorted flowers.