The Commercial Greenhouse Needs Assessment Survey-1991 was mailed to 201 greenhouse firms throughout Colorado in Aug. 1991. One-hundred-twenty-two usable surveys were returned, a return rate of 61%. The survey contained four sections: Educational Programming Topics; Educational Program Delivery Methods; Needs Other Than Classes; and Personal/Business Data. Results of the Programming Topics section indicated that non-chemical pest control was the subject of most interest (70.6% of respondents), followed by chemical pest control (62.2%). Results of the Programming Delivery Methods section showed that greenhouse operators most wanted workshops (77. 1%). A monthly format (54.7%) was preferred, with evenings (41 .4%) the best time. The Needs Other Than Classes section indicated that greenhouse operators across the state expected visits from the Commercial Greenhouse Extension Agent on an as-needed basis (59.6%), and that 39.2% of the survey respondents were aware of services available from the Commercial Greenhouse Extension Agent. The Personal/Business section indicated that most respondents had a bachelor's or master's degree (53.3%), and were wholesale growers (66.9%) with greenhouses < 50,000 ft2 (67.5%).
Karen L. Panter
Karen L. Panter
Between Dec. 1992 and July 1993, 13 greenhouse operations took part in on-site training programs concerning pesticide application safety. Each program involved a pre-quiz, post-quiz, presentation of two videotapes, discussion, session evaluation, and follow-up evaluation 1 month after each session. A total of 253 Colorado greenhouse employees participated in the programs, which fulfilled the employee training requirements for the Occupational Safety and Health Administration's Hazard Communication standard concerning hazardous materials in the workplace. Quiz scores increased from the pre- to the post-program quiz, from 17.3 to 22.1 points out of a possible 27. Post-program evaluations indicated that the vast majority of respondents either “agreed” or “strongly agreed” that (percentages in parentheses): “the training program will be helpful” (85%), “I understand hazardous materials better” (81%), “the training videos helped understanding” (84%), and “I would like the training done regularly” (79%). Follow-up evaluations showed that most “agreed” or “strongly agreed” that (percentages in parentheses): “I have used at least one new safe handling practice” since the program (55%), and “I plan to use more” safe handling practices (82%). This method of instructing employees about hazardous materials would be applicable to others interested in safety issues.
Karen L. Panter
The objective of this study was to determine if hemiparasitic Castilleja (Indian Paintbrush) could be successfully sown and grown in the same containers with each of three host plants. Perennial Castilleja linariifolia, Wyoming's state flower, was sown in combination with either Helianthus annuus `Pacino', Lupinus `Russell Mix', or Artemisia frigida. Seeds were sown 7 Oct. 1999 in 128-cell plug trays. Trays were then placed on a mist propagation bench at 21 °C until emergence of any plant species was evident. Artemisia emerged 12 Oct.; Lupinus and Helianthus emerged 13 Oct. Plug trays were then transferred to a greenhouse at 13 °C night/21 °C day temperatures under natural light conditions. Plugs were transplanted into 11.4-cm-diameter containers on the following dates: C. linariifolia/Helianthus–12 Nov.; C. linariifolia/Lupinus–18 Nov.; and C. linariifolia/Artemisia–2 Dec. C. linariifolia emerged, after transplanting, on 16 Dec. All three combinations were successfully produced in the greenhouse.
Karen L. Panter
Two studies were undertaken to quantify the amount of water used by two container-grown bedding plant crops. Petunia × hybrida cv. Welby Blue and Pelargonium × hortorum cv Red Satisfaction plants were grown in 11-cm pots in a commercial greenhouse in Denver, Colo. In Expt. 1, rooted geranium cuttings and petunia seedlings were planted in Fafard #2, a growing medium containing peat, perlite, and vermiculite. Half of the plants were grown with the substrate covered. Each pot was weighed just prior to, and again 24 h, after watering. Measured amounts of water were applied to the pots. Geraniums in uncovered pots lost an average of 1.7 kg/pot over 59 days. Geraniums in covered pots lost an average of 1.6 kg/pot. Petunias, over 23 days, lost 730 g per uncovered pot and 623 g per covered pot. Experiment 2 compared water loss in growing medium amended with five different hydrophilic gels, and a control with no gel added. With geraniums, no differences were found among treatments in total water loss, initial or final plant height, or fresh or dry plant weight. With petunias, no differences occurred in initial or final height, or fresh or dry weight. There was a difference between two of the gel treatments in total amount of weight lost.
Karen L. Panter
A study was undertaken between June 30 and September 15, 1993 to determine the effects of five different hydrophilic gels on petunia `Supercascade Red' dry weights, stem lengths, and bud counts. Data were compiled on growing medium and plant tissue analyses as well as days between waterings of gel-amended versus control media. A completely randomized design was utilized with six treatments (five gels and control), 15 pots per treatment, five plants per ten-inch banging basket. Statistical analyses showed no significant differences either within or among treatments for stem lengths or bud counts, or among treatments for plant dry weights. Two cases of significant differences among pots within treatments did occur. Plant tissue analyses run before and after the study showed consistent increases in N, P, Ca, Mg, S, Zn, and B; decreases in Fe, Cu, and Na; and mixed changes in K and Mn over the 11-week study. Growing medium analyses run before and after the study showed consistent increases in Fe; decreases in EC, % organic matter, NH4-N, K, Mg, SO4 S, Mn, and Cu; and mixed changes in pH, NO3-N, P, Ca, and Zn. There were no significant differences in either the number of waterings or the days between waterings among the six treatments.
Karen L. Panter
Interest in horticulture in Wyoming increases each year. The vast size of the state, coupled with its low population, make travel to individual sites around the state difficult. Distance education and communication are keys to a successful horticulture Extension education program. Every summer since 2000, the University of Wyoming Cooperative Extension Service has sponsored a series of horticulture question and answer sessions. These sessions are carried out using the Wyoming compressed video system, linking campus-based specialists with Extension educators, Master Gardeners, industry, and occasionally the public, around the state. The number of sites linked with campus has varied from six to 11, depending on the year. The number of sessions held each summer has also varied, from the current six to a high of nine in 2000. Each session is 50 minutes long. The objective of these sessions is to allow personnel off-campus to show samples, ask questions, and get assistance from campus-based specialists in diagnosing various plant problems. Evaluations are done annually to determine several things: if the programs should be run again the next year, which days of the week and time of the day are best, if attendees are utilizing the information learned in the sessions, and if they feel more comfortable with their own diagnoses after the sessions. Responses vary with year, but typically 100% say the programs should continue, and greater than 75% use the information they learn and are more comfortable with their responses and their abilities to solve plant problems.
Bennett J. Sondeno and Karen L. Panter*
Osha (Ligusticum porteri) is a Rocky Mountain native used as a medicinal herb. Studies are underway to commercially propagate and produce the plant. In an attempt to increase rooting success of crown cuttings taken from osha, five different media were used in conjunction with three commercial mycorrhizal inoculants and a control. Field soil and a pre-mixed commercial product were tested in combinations of 100/0, 75/25, 50/50, 25/75, and 0/100 percent by volume. Each of three commercially-available mycorrhyzal inoculants were tested with each media. Crown cuttings of osha were taken and stuck on 29 Aug. 2003 and were placed on a greenhouse mist bench. Data were taken on days to rooting. Results showed no differences among the media or the inoculants and no interactions were present. There was no benefit in decreased days to rooting with additions of mycorrhizae. There were no responses to different media.
Andrea R. Garfinkel and Karen L. Panter
The objective of this study was to determine the potential for year-round greenhouse production of specialty cut sunflowers (Helianthus annuus) in Wyoming. Over a 14-month period, we produced cut sunflowers in a nontraditional, transplant-based, potted method using natural light intensity and daylength conditions in Laramie, WY. Three cultivars of annual sunflowers, Dafna, ProCut Bicolor, and Sunbright Supreme, were grown from seeds sown at 2-week intervals starting on 16 Nov. 2011. Each planting consisted of four replications of four plants each. Seedlings were transplanted into 550-mL square plastic pots 15 days after sowing and were placed on greenhouse benches in blocks according to sow date. Flowers were cut at soil level when ray florets opened. Data collected included days to harvest and stem length for each stem. Results indicated significant cultivar by sow date interactions for days to harvest and stem lengths, indicating the importance of cultivar selection. Mean days to harvest ranged from 57 days (‘Sunbright Supreme’) to 103 days (‘ProCut Bicolor’). Mean stem lengths ranged from 43 cm (‘Dafna’) to 153 cm (‘Sunbright Supreme’). Overall, the results of this study show potential for year-round production of cut sunflowers and can help guide producers in the Rocky Mountain west to choose cultivars that best fit the needs of their business and market demand.
Laura Pickett Pottorff and Karen L. Panter
With the cooperation of six commercial greenhouses (five in Colorado, one out of state), rooted poinsettia cuttings and bedding plant plugs were collected and analyzed for Pythium and Rhizoctonia, two common root rotting pathogens in Colorado greenhouses. Samples of plant, soil, and water debris were taken from four greenhouses, as well as samples of growing media ready for use. These were also analyzed for Pythium and Rhizoctonia. Fungi recovered from the plant, debris, or growing media samples were identified, grown in pure culture, and introduced into susceptible plants (Vinca minor) in pathogenicity studies. Neither pathogen was isolated from the rooted poinsettia cuttings tested. Pythium was not found in any of the plug material or in growing media. Rhizoctonia solani was found in 16% of the plug samples and 7% of the growing media samples tested. Debris from greenhouse floors yielded four species of Pythium as well as Rhizoctonia solani. Isolates of each fungus were able to colonize, but not adversely affect, inoculated plants in pathogenicity studies. It appears that disease causing organisms that have potential to decrease plant quality and growth are already present in the greenhouse. Control of root rotting pathogens can best be carried out by relying heavily on sanitation measures.