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- Author or Editor: William Carlson x
There are over 11,000 greenhouse growers in the United States. Of this number, 8,000 produce less than $500,000 per year in total sales. Less than 1% of the 11,000 have a strategic business plan. Many may have a yearly budget, but they have not developed a formal written analysis of their business in relation to internal and external factors. A sample of 10 growers indicated that their profitability increased significantly when they understood a formal strategic business plan. The information developed from this sample indicates the entire greenhouse industry could benefit greatly from increased use of strategic planning. The marketing component of the business plan and how university personnel can facilitate this effort will be discussed.
Abstract
The poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch) cultivar ‘Stoplight’ was introduced to the floriculture industry in 1965 by Robert N. Stewart, U.S.D.A. at Beltsville, Maryland. The sub-terminal bracts of the cultivar have coloration in addition to those located terminally. ‘Stoplight’ is the first poinsettia cultivar noted for this type of bract coloration, and recent hybrid poinsettia introductions inherit this plant characteristic from ‘Stoplight’ parentage (2).
Abstract
The influence of B-Nine (2500 ppm), F 529 (1250 ppm), TIBA (250 ppm), IAA (100 ppm), Ethrel (1000 ppm), Cycocel spray (1475 ppm) and soil drench (2950 ppm) were investigated on seed propagated geranium, cv. ‘Carefree Scarlet’. IAA had no effect on date of flowering, plant height or branching, but TIBA sprayed plants flowered significantly earlier and Ethrel sprays significantly delayed it. Both TIBA and Ethrel sprays reduced geranium height at flowering and stimulated branching. A Cycocel soil drench caused earlier flowering, but sprays had no effect on flowering. In growth chambers with 12-hour light periods of 75 F and 12-hour dark periods of 70 F, 60 F, or 50 F, earliest flowering was at 70 F with 5 and 15 days delays at 60 F and 50 F. The number of nodes of terminal stems at flowering increased from 14 at 70 F to 16 at 60 F and 17 at 50 F night temperatures.
Abstract
The effects of daylength during the 63°F lily rooting period prior to 40° storage and the duration and scheduling of the storage period were determined for Japanese-grown ‘Georgia’ lilies. Benefits from the Controlled Temperature Forcing (CTF) method for increased flower buds and leaves were lost if used with 16-hr day lengths during the 63° period before storage. Artificial fluorescent light of 5 watts per ft2 to create a 16-hr daylength was found adequate to reduce the CTF effects. The length of the 63° period prior to cold treatment affected the days from bulb planting to flowering, no. of flowers, plant height, and no. of leaves. These results were similar at both the 10 and 16-hr day lengths. The effects of 6 week 40° cold period decline at both photoperiods as the duration of the 63° period before storage increases. Delaying the 40° cold period until 10 weeks after planting at the 16-hr daylength resulted in flowering only 4 days before lilies receiving no cold treatment.
Seeds of eight commonly grown bedding plant species [Ageratum houstonianum Mill., Begonia × semperflorens Hort., Impatiens wallerana Hook., Lobularia maritima (L.) Desv., Petunia × hybrida Hort., Pelargonium hortorum L.H. Bailey, Salvia splendens F. Sellow, Tagetes patula] were germinated at pH values from 4.5 to 7.5 at 0.5 increments. Seeds were germinated in petri dishes on filter paper saturated with buffer solutions or in petri dishes containing a 50 sphagnum peat: 50 coarse vermiculite (peatlite) medium moistened with buffer solutions. Germination on filter paper was affected by pH for all species tested. Peatlite medium pH affected germination of all species tested, except Salvia splendens. Species response to similar pH values differed between the two germination procedures. Total percent germination of seeds germinated was less in peatlite medium than on filter paper.
The effects of 5 day temperatures (15-35 C), 5 night temperatures (15-35 C), and 3 light levels (50% shade, ambient, and supplemental light) were determined for Catharanthus roseus cv. `Grape Cooler', Average Daily Temperature (ADT) was calculated for the 25 day/night temperature combinations. As ADT increased, time to flower decreased with the shortest time to flower at an ADT of 32.5 C. Plants grown without supplemental light and with an ADT of 17.5 C or less did not flower at the termination of the experiment (110 days from seeding). Plants grown under higher ADT also had a higher leaf unfolding rate (LUR) than plants grown under the lower ADT. The increase in LUR was linear over the entire temperature range of 15-35 C. Application of supplemental lights increased shoot fresh weight and decreased time to flower.
Effects of temperature (18-32C), irradiance (0-4.3 mol day-1m-2), and pH (4.5-7.5) on germination of begonia were evaluated. Germination of 90-93% occurred at 18-24C and 79-83% at greater than 24C. There was no difference in germination between seeds receiving ambient irradiance conditions and seeds receiving 24hr supplemental irradiance (4.3 mol day-1m-2). Begonia did not germinate in the dark. On filter paper, no germination occurred at pH 4.5 or 5.0 while germination of 84 and 94% occurred within the pH range 5.5-7.5. In a peatlite medium, germination ≥80% occurred across all pH levels evaluated.
Photosynthetic photon flux (PPF), day temperature (DT), and night temperature (NT) effects on vegetative development (3 true leaves to first flower) were determined. Plant height increased <2 cm as PPF level increased from 4.4 mol day-1m-2 to 12.15 mol day-1m-2. DT and NT influenced plant height, but as with PPF, the differences were only 1-2 cm. Neither average daily temperature (ADT) nor the difference between the DT and NT (DIF) affected plant height. Primary lateral shoot number increased as temperature and PPF increased.
Previous research has shown that the photoperiod under which stock plants are grown has a significant effect on cutting production and rooting of several species of herbaceous perennials. Long-day (LD) treatment of stock plants promoted cutting production of certain LD perennials but reduced rooting. Cuttings from plants grown under short days rooted readily but few were produced. Stock plants were exposed to alternating photoperiods to determine if this treatment would yield many cuttings with high rooting potential. Coreopsis verticillata `Moonbeam' and Phlox paniculata `Eva Cullum' stock plants were given 4 weeks of 4-h night interruption (NI), while Sedum `Autumn Joy' stock plants were grown under 14-h days. After 4 weeks plants were given 0, 2, or 4 weeks of 10-h days. Cuttings were harvested and propagated under mist and three different photoperiods (10-h, 14-h, NI) for 4 weeks, after which rooting percentage and the number and length of roots produced by each cutting were measured. The results will be presented.