830 PB 314 FORCING HERBACEOUS PERENNIALS TO FLOWER AFTER STORAGE OUTDOORS BENEATH A THERMOBLANKET

Nine herbaceous perennial species were evaluated for use as flowering pot plants for late winter and early spring sales. Plugs of Achillea `King Edward', Arabis sturii, Armeria `Alba', Bergenia `New Hybrid', Chrysogonum virginianum, Dianthus `War Bonnet', Phlox `Chattahoochee', Platycodon `Sentimental Blue', and Veronica `Sunny Border Blue' were established in 14-cm (0.8-liter) round plastic containers, grown for one season, and covered with a thermoblanket for winter. Five plants of each species were transferred to a 21 ± 3C glasshouse for forcing under natural daylength at six 10-day intervals beginning 1 Dec. 1993. By this date plants had experienced approximately four weeks of temperatures below 5C. Ambis, Chrysogonum, and Phlox, species that naturally flower in spring, were the most floriferous. Days to first flower for Arabis decreased from 30 to 26 while flower number increased 44% by the 20 Dec. forcing date. For Phlox, days to first flower decreased from 36 to 31 by 20 Dec., but flower numbers were similar regardless of forcing date. Chrysogonum averaged eight flowers throughout the study, but days to first flower increased from 25 (1 Dec.) to 31 in all following forcing dates.

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Forcing Herbaceous Perennials to Flower after Storage Outdoors under a Thermoblanket

HortTechnology ◽

10.21273/horttech.5.3.239 ◽

1995 ◽

Vol 5 (3) ◽

pp. 239-243

Author(s):

Jeffery K. Iles ◽

Nancy H. Agnew

Keyword(s):

Early Spring ◽

Late Winter ◽

Perennial Species ◽

Potted Plants ◽

Herbaceous Perennials ◽

Armeria Maritima ◽

Supplemental Lighting ◽

Floral Displays ◽

Plastic Containers ◽

Herbaceous Perennial

Nine herbaceous perennial species were evaluated for use as flowering potted plants for late winter and early spring sales. Plugs of `King Edward' Achillea × Lewisii Ingw. (yarrow), Arabis sturii Mottet. (rockcress), `Alba' Armeria maritima (Mill.) Willd. (common thrift), `New Hybrid' Bergenia cordifolia (Haw.) Sternb. (bergenia), Chrysogonum virgianum L. (goldenstar), `War Bonnet' Dianthus × Allwoodii Hort. Allw. (Allwood pinks), Phlox × chattahoochee L. (Chattahoochee phlox), `Sentimental Blue' Platycodon grandiflorus (Jacq.) A. DC. (balloonflower), and Veronica L. × `Sunny Border Blue' (veronica) were established in 14-cm (0.8-liter) round plastic containers, grown for one season and covered with a thermoblanket for winter. Five plants of each species were transferred to a 21 ± 3C glasshouse for forcing under natural daylengths at six 10-day intervals beginning 1 Dec. 1993. Arabis sturii, Phlox × chattahoochee, Platycodon grandiflorus `Sentimental Blue', and Veronica × `Sunny Border Blue' flowered out of season without supplemental lighting. `Alba' Armeria maritima and Chrysogonum virginianum also flowered; however, their floral displays were less effective. `New Hybrid' Bergenia cordifolia did not flower and `King Edward' Achillea × Lewisii and `War Bonnet' Dianthus × Allwoodii only flowered sporadically, therefore, these perennials are not recommended for forcing out of season using our vernalization method.

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The Response of Long-day Herbaceous Perennials to a Night-interruption at Low Night Temperatures

HortScience ◽

10.21273/hortsci.32.3.484d ◽

1997 ◽

Vol 32 (3) ◽

pp. 484D-484

Author(s):

Alison Frane ◽

Royal Heins ◽

Art Cameron ◽

William Carlson

Keyword(s):

Low Temperature ◽

Early Spring ◽

Perennial Species ◽

Treatment Results ◽

Flower Bud ◽

Herbaceous Perennials ◽

Long Day ◽

Node Count ◽

Herbaceous Perennial ◽

Short Days

A 4-hr night interruption (NI) is an effective way to promote flowering in many long-day herbaceous perennials. Some perennials are grown outdoors in the early spring and often are exposed to low night temperatures. Long days delivered by NI lighting ineffectively promote flowering under low-temperature conditions in some long-day species. The objective of this experiment was to determine the effectiveness of NI long-day lighting treatments delivered at different night temperatures in promoting flowering of several herbaceous perennials. Ten herbaceous perennial species were grown under natural short days augmented with a 4-hr NI. Night temperatures were 2.5, 5, 10, 15, 20, and 25°C with day temperature of 25°C for all treatments. Plants were transferred to 9-hr days at a constant 20°C after 7 weeks of treatment. Results on flowering percentage, date of visible bud and flowering, node count, flower bud count, and plant height at flowering will be presented.

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391 THE INFLUENCE OF COLD DURING SEEDLING STAGE AND PHOTOPERIOD ON FORCING PERENNIALS FOR POT PLANTS

HortScience ◽

10.21273/hortsci.29.5.487b ◽

1994 ◽

Vol 29 (5) ◽

pp. 487b-487

Author(s):

Allan M. Armitage ◽

Paul Thomas

Keyword(s):

Plant Height ◽

Early Spring ◽

Seedling Stage ◽

Internode Elongation ◽

Perennial Species ◽

Photoperiodic Treatment ◽

Short Days ◽

Pot Plants

The influence of cooling, photoperiod and chemical branching on early spring flowering of perennial species was studied. Cooling was provided while plants were in plugs (128 plugs per tray) and dikegulac-sodium, a compound found to induce breaks in other species, was applied prior to, during and after cooling. Plants were cooled in insulated lighted coolers for 4, 8 or 12 weeks at 4C, and brought to a greenhouse with night temperatures between 8-12C. Long and short days were provided in the greenhouse after plants came out of the coolers. Little response to dikegulac occurred, however, Campanula, Sedum, Leontopodium, Catananche, Aubrietia, Arabis, Gypsophila, Anchusa and Aquilegia responded to cooling and photoperiodic treatment. Flowering and vegetative characteristics such as internode elongation and plant height responded to photoperiod and cooling but not all genera responded similarly. Anchusa, Campanula, Aquilegia and Gypsophila flowered significantly earlier under LD compared to SD. Twelve weeks of cooling resulted in flowering of all genera, however, some genera were equally responsive to shorter cooling times.

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Cold Treatments Alter the Photoperiodic Flowering Response of Some Herbaceous Perennial Species

HortScience ◽

10.21273/hortsci.33.3.508c ◽

1998 ◽

Vol 33 (3) ◽

pp. 508c-508

Author(s):

Erik S. Runkle ◽

Royal D. Heins ◽

Arthur C. Cameron ◽

William H. Carlson

Keyword(s):

Cold Treatment ◽

Cold Period ◽

Photoperiodic Induction ◽

Perennial Species ◽

Additional Species ◽

Flowering Response ◽

Herbaceous Perennials ◽

Photoperiodic Flowering ◽

Herbaceous Perennial ◽

Short Days

Many species of herbaceous perennials either require a cold treatment for flowering or exhibit enhanced and more desirable flowering characteristics following a cold period. For some species, the photoperiodic induction of flowering can change following cold treatments, the parameters generally becoming less strict as plants receive longer durations of cold until a saturation duration is reached. To quantify the minimum and saturation durations of cold for flowering under short days (SD) and long days (LD), five species were selected and cooled for 0, 3, 6, 9, 12, or 15 weeks at 5 °C, then forced at 20 °C under 9-h photoperiods without (SD) or with a 4-h night interruption (LD). The effects of cold and photoperiod on flowering varied by species. For example, under SD, 0%, 80%, or 100% of Leucanthemum xsuperbum `Snowcap' flowered after 0, 3, or ≥6 weeks at 5 °C, respectively, and time to flower decreased from 103 to 57 days as the duration of cold increased from 3 to 12 weeks. `Snowcap' cooled for ≥3 weeks, then forced under LD, flowered completely in 45 to 55 days. Flowering percentage of Lavandula angustifolia `Hidcote' reached 100 under LD or SD only when plants were cooled for ≥6 or 15 weeks, respectively. Under LD, flowering percentage of Astilbe chinensis pumila progressively increased from 0 to 100 as cold treatment increased from 0 to 15 weeks; flowering percentage under SD was low regardless of cold treatment. Additional species and flowering characteristics will be discussed.

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Evaluation of Structureless Overwintering Systems for Container-Grown Herbaceous Perennials

Journal of Environmental Horticulture ◽

10.24266/0738-2898-11.2.48 ◽

1993 ◽

Vol 11 (2) ◽

pp. 48-55

Author(s):

Jeffery K. Iles ◽

Nancy H. Agnew ◽

Henry G. Taber ◽

Nick E. Christians

Keyword(s):

Low Temperature ◽

Plant Growth ◽

High Temperatures ◽

Early Spring ◽

Late Winter ◽

Temperature Extremes ◽

Plant Survival ◽

Herbaceous Perennials

Abstract Five structureless overwintering systems were evaluated for temperature moderation and protection of 18 container-grown herbaceous perennials from low-temperature injury. Two light-excluding treatments; 30 cm (1 ft) of straw between two layers of 4-mil white polyethylene and 18 cm (7 in) deep, in-ground beds protected with one layer of 4-mil white polyethylene and 30 cm (1 ft) of woodchips, provided the greatest moderation of winter low and early spring high temperatures, but also resulted in severe etiolation. A bonded white polyethylene/microfoam overwintering blanket (thermoblanket) with translucent properties provided comparable plant survival percentages despite dramatic temperature extremes recorded beneath this cover and, in late winter, created an environment conducive to moderate plant growth without formation of etiolated tissue.

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Weed Control Strategies for Field Grown Herbaceous Perennials

Journal of Environmental Horticulture ◽

10.24266/0738-2898-14.4.221 ◽

1996 ◽

Vol 14 (4) ◽

pp. 221-227

Author(s):

James B. Calkins ◽

Bert T. Swanson ◽

Debra L. Newman

Keyword(s):

Weed Control ◽

Production Systems ◽

Control Strategies ◽

Wood Chip ◽

Early Spring ◽

Herbicide Application ◽

Control Efficacy ◽

Herbaceous Perennials ◽

Growing Conditions ◽

Herbaceous Perennial

Abstract Fourteen herbicides or herbicide combinations, wood chip mulch, chipped rubber tire mulch, and newspaper mulch were evaluated for weed control efficacy and phytotoxicity using 12 species of herbaceous perennials under field growing conditions. The effect of herbicide application time was monitored by applying herbicides to dormant and actively growing plants. Herbicide and mulch treatments were compared to weeded and non-weeded controls. Herbicide phytotoxicity was dependent on age and species of herbaceous perennial and time of herbicide application. Herbicide injury was generally greater for young plants compared to established plants and phytotoxicity was usually reduced when herbicides were applied to dormant rather than actively growing plants. Injury was sometimes greater when herbicides were applied in early spring compared to applications made after complete herbaceous perennial emergence. Injury to young shoots that had emerged prior to the earliest possible time that herbicides could be applied in the spring was probably involved. Applying herbicides in the fall may avoid such injury. Mulching field grown perennials with wood chips provided the most effective weed control and often the best quality plants. With the exceptions of Hemerocallis ‘After Dark’ and Phlox maculata ‘Omega’, the herbaceous perennials evaluated were tolerant of most of the herbicides applied. Several herbicides, including Balan 2.5G at 3.36 kg ai/ha (3.0 lb ai/A), Snapshot 80DF at 4.48 kg ai/ha (4.0 lb ai/A), and Stomp 60WDG at 4.48 kg ai/ha (4.0 lb ai/A), demonstrated potential for weed control in herbaceous perennial production systems and landscape plantings. Goal 1.6EC at 1.68 kg ai/ha (1.5 lb ai/A) and Ronstar 50WP at 3.92 kg ai/ha (3.5 lb ai/A) were often phytotoxic when applied to herbaceous perennials.

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Effects of Temperature, Photoperiod, and Light Quality on Flowering in Several Herbaceous Perennial Species

HortScience ◽

10.21273/hortsci.30.4.771d ◽

1995 ◽

Vol 30 (4) ◽

pp. 771D-771

Author(s):

Catherine Whitman ◽

Royal Heins ◽

Arthur Cameron ◽

William Carlson

Keyword(s):

High Pressure ◽

Low Temperatures ◽

Light Quality ◽

Perennial Species ◽

Flower Number ◽

Lavandula Angustifolia ◽

Sporadic Flowering ◽

Effects Of Temperature ◽

Herbaceous Perennial ◽

Campanula Carpatica

The influence of low temperatures on Campanula carpatica `Blue Clips' and Lavandula angustifolia `Munstead' flowering was determined; plants were stored at 5C for several weeks and forced under 9-h photoperiods with a 4-h night interruption (NI). C. carpatica, L. angustifolia, and Asclepias tuberosa were forced under NI at five temperatures (15–27C) and time to flower under each treatment was calculated. Flower number and size were reduced at highest temperatures. The effectiveness of cool-white fluorescent (CWF), high-pressure sodium (HPS), incandescent (I), and metal halide (MH) lights in inducing flowering in C. carpatica and Coreopsis lanceolata `Early Sunrise' was compared. Lighting was delivered as a 7-h daylength extension with PPF ranging from 0.05–2.0 μmol·m–2·s–1. Minimum irradiances above which all C. carpatica flowered were approximately 0.14, 0.12, 0.1, and 0.17 μmol·m–2·s–1, respectively. C. lanceolata under CWF displayed irregular flowering throughout the range of intensities used. Under HPS and MH, minimum irradiances for 100% flowering were 0.37 and 1.0 μmol·m–2·s–1, respectively, with sporadic flowering at lower intensities. Under I light, all C. lanceolata exposed to 0.12 μmol·m–2·s–1 or more flowered.

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Influence of Daylength Delivery on Flowering in Several Herbaceous Perennial Species

HortScience ◽

10.21273/hortsci.30.4.861f ◽

1995 ◽

Vol 30 (4) ◽

pp. 861F-861

Author(s):

Cheryl Hamaker ◽

William H. Carlson ◽

Royal D. Heins ◽

Arthur C. Cameron

Keyword(s):

Continuous Light ◽

Flower Induction ◽

Perennial Species ◽

Herbaceous Perennials ◽

Short Day ◽

Long Day ◽

Herbaceous Perennial ◽

Campanula Carpatica

To determine the most effective lighting strategies for flower induction of long-day (LD) plants, 10 species of herbaceous perennials were chilled at 5C for 0 or 12 weeks and then forced at 20C under the following photoperiods: short day, 4-h night interruption (4-h NI), 7-h night interruption (7-h NI), 7-h day extension, 7-h predawn (7-h PD), and 24-h continuous light (24-h). All treatments consisted of a 9-h photoperiod of sunlight supplemented with 90 μmol·m–2 from HPS lamps. LD treatments were delivered by incandescent lights and induced flowering in obligate LD plants. Rate of flowering, height, and bud number at first flower varied among species and LD treatments. Although flowering was accelerated under 24-h and 7-h NI for most species, it was delayed under 24 h for Coreopsis verticillata `Moonbeam' and Campanula carpatica. For unchilled plants of most species, flowering was delayed under 7-h PD compared to other LD treatments. Chilling decreased time to flower and reduced differences between LD treatments. Coreopsis `Moonbeam' and C. Ianceolata `Early Sunrise' were shorter when grown under 4-h NI.

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Pot-in-Pot Production of Six Intermountain West Native Herbaceous Perennial Species Grown in Containers

Journal of Environmental Horticulture ◽

10.24266/0738-2898-24.2.77 ◽

2006 ◽

Vol 24 (2) ◽

pp. 77-83

Author(s):

Guillermo Cardoso ◽

Roger Kjelgren ◽

Teresa Cerny-Koenig ◽

Rich Koenig

Keyword(s):

Stomatal Conductance ◽

Water Loss ◽

Root Zone ◽

Intermountain West ◽

Perennial Species ◽

Root Zone Temperature ◽

Herbaceous Perennials ◽

Lower Elevation ◽

Production Cycles ◽

Herbaceous Perennial

Abstract We investigated the performance of six Intermountain West (IMW) native herbaceous perennial species grown in a pot-in-pot (PIP) or conventional above-ground (CAG) production system for two years. Three different species were grown for two production cycles each year. Root zone temperature (RZT), plant and container water loss, stomatal conductance, plant height, and final biomass were measured. The RZT of plants in the PIP system were as much as 7C cooler than the CAG system, with temperature differences greater at the edge than at the center of the container. Water loss was approximately 10% lower for PIP plants on five of eight measured dates despite higher stomatal conductance on five of seven dates. Higher RZT and lower gas exchange reduced top growth more than root growth for CAG produced plants, but results varied with species and season. Conventional above-ground plants showed no visible damage but had slower growth rates compared to PIP plants. Lower elevation species were more tolerant of warmer above ground RZT, but more susceptible to winter damage. Results indicate that in areas with severe yearly temperature extremes, higher quality IMW herbaceous perennials could be grown with the PIP system in #1 containers compared to the CAG system.

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Seed dormancy and germination of three herbaceous perennial desert ephemerals from the Junggar Basin, China

Seed Science Research ◽

10.1017/s096025850999002x ◽

2009 ◽

Vol 19 (3) ◽

pp. 183-189 ◽

Cited By ~ 8

Author(s):

An-jun Tang ◽

Mei-hua Tian ◽

Chun-lin Long

Keyword(s):

Soil Moisture ◽

Seed Germination ◽

Junggar Basin ◽

Early Spring ◽

Herbaceous Perennials ◽

Spring Ephemeral ◽

Temperate Desert ◽

Herbaceous Perennial ◽

Germination Cues ◽

Seed Dormancy And Germination

AbstractThe purpose of our study was to better understand seed germination ecology of the spring ephemeral herbaceous perennials,Ixiolirion tataricum,Tulipa iliensisandScorzonera pusilla, in the temperate desert in the Junggar Basin of northwestern China. Seeds ofI. tataricum,T. iliensisandS. pusillawere dormant at maturity but when subjected to cold, dry (2 months at 4°C) followed by cold, wet ( ≤ 40 days at 4°C) conditions, they germinated to 100%, 96% and 93%, respectively. After 2 months' dry storage at 4°C, seeds germinated to only 11%, 3% and 42%, respectively at 15°C, and no seeds germinated at 30°C. Seeds of the three species were not sensitive to light. Low ( < 12.7%) and high (21.4%) soil moisture contents suppressed germination. In addition, both final germination percentages and rates of the three species decreased dramatically with a decrease in water potential from 0 to − 3.17 MPa. Thus, the low-temperature requirement for dormancy break and germination cues seed germination to occur in early spring when soil moisture is favourable for germination and subsequent seedling establishment.

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