Seedlings of processing tomato `H 2653' (Lycopersicon esculentum Mill.) were cultured in 288-cell (< 6 cm3 volume) plug trays in a soilless growing medium. Pretransplant fertilization with nutrient solutions containing 10 or 20 mm N and 2 or 5 mm P for 10 days altered the total ammoniacal-N and P, and the soluble NO3-N and PO4-P concentrations in the shoot tissue at transplanting. Post-transplanting shoot and root growth were more rapid in late May plantings than in earlier plantings. The 20-mm N and 2-mm P pretransplant treatment caused the most rapid shoot growth following early season plantings in the field. Rapid seedling establishment after transplanting was generally not a good indicator of potential fruit yield. The 5-mm P pretransplant treatment produced higher marketable fruit yields in early plantings but not in later. Culture of seedlings under a low fertilization regime (5.4 mm N, 1.0 mm P, and 1.6 mm K) before pretransplant treatment produced as high or higher fruit yields than did seedlings from a higher regimen. Withholding fertilizer temporarily before transplanting resulted in a depletion in tissue N and P concentrations, slow post-transplanting shoot growth, and lower yields.
Ronald W. Garton and Irvin E. Widders
Kathryn M. Kleitz, Marisa M. Wall, Constance L. Falk, Charles A. Martin, Marta D. Remmenga, and Steven J. Guldan
herbs. The purpose of this study was to compare direct seeding to transplants for plant establishment, and to find the number of marketable harvests and the yield for five herbs: calendula, catnip, lemon balm, stinging nettle, and globemallow. Materials
Tian Gong, Xin Zhao, Ashwin Sharma, Jeffrey K. Brecht, and James Colee
tomato transplants. Materials and methods Experiments were carried out in Spring 2018 and Summer 2019. The 2018 experiment was a pilot study comparing a chamberless healing method with other healing treatments of grafted tomato. The 2019 experiment was
Elizabeth T. Maynard
In a wet spring, transplants must often be held beyond the planned transplant date. The plants become overgrown, making mechanical transplanting difficult. We compared several ways of holding `Mountain Spring' tomato (Lycopersicon esculentum L.) transplants. Transplants were 1) planted outside on planned transplant date in late May (NH), 2) held outside for 2 weeks (HOF), 3) held outside for 2 weeks and not fertilized during that period (HONF), and 4) held in the greenhouse for 2 weeks (HGF). Throughout transplant production, half of the transplants in each holding treatment were fertilized with 100 ppm N and half with 25 ppm N from 20N-4.4P-17K or 15N-2.2P-12.3K. HONF reduced plant height 1.7 to 1.5 cm compared to HOF or HGF. Plants grown with 25 ppm N were 5 to 6.4 cm shorter than plants grown with 100 ppm N and showed symptoms of nutrient deficiency. On average, holding treatments reduced marketable yield 20% to 23% and early yield 31% to 37%, compared to NH. HOF and HGF produced similar marketable yield, early yield, and fruit size. HONF decreased early yield in 1997 and decreased marketable yield in 1998, compared to HOF. The differences between holding treatments were usually greater with 100 ppm N. Plants grown at 25 ppm N produced lower marketable and early yields and larger fruit than 100 ppm N. The best method for holding transplants among those tried here is to put them outdoors and continue fertilizing as during transplant production.
Daniel J. Cantliffe
Transplants are grown and shipped locally or over long distances. Shipping conditions and time in transit depend on the distance travelled. Local growers may receive transplants in trays they were grown in while those shipped long distances are pulled and packed in boxes. Plant field performance is directly correlated with seedling vigor at the time of transplanting. Factors which can affect transplant vigor during growing and shipping include the plant hardening techniques employed, mechanical injury at any stage of plant growing, shipping and planting, length and conditions of transit, and storage prior to transplanting. Mechanical injury begins as soon as the plants are removed from the tray, while reduced watering and/or nutrition during hardening may have a long term effect on plant productivity. High temperature during shipping, packing plants too densely, and prolonged storage in the dark can reduce subsequent yields. Knowledge of proper conditions for transplant pre- and post-harvest handling and shipping are not clearly understood by many transplant producers and growers. Such knowledge can greatly improve transplant vigor and potentially give growers better yields.
Charles S. Vavrina
The research reviewed here represents the majority of the information available on transplant age to date. When the results of these studies are distilled down to the “ideal” transplant age for setting of a specific crop, we generally arrive at the recommendations found in the 1962 edition of Knott's Handbook for Vegetable Growers. The conflicting results in the literature on transplant age may be due to the different environmental and cultural conditions that the plants were exposed to, both in the greenhouse and in the field. The studies did reveal that the transplant age window for certain crops might be wider than previously thought. Older transplants generally result in earlier yields while younger transplants will produce comparable yields, but take longer to do so. Our modern cultivars, improved production systems, and technical expertise enable us to produce high yields regardless of transplant age. The data, in general, support the view that if a vegetable grower requires resets after an catastrophic establishment failure (freeze, flood, etc.), they need not fear the older plants usually on hand at the transplant production facility.
Anne-Marie Hanson, J. Roger Harris, Robert Wright, Alex Niemiera, and Naraine Persaud
Newly transplanted container-grown landscape plants are reported to require very frequent irrigation. However, container nurseries in the U.S. commonly use growing substrates that are mostly bark, even though the contribution of bark-based growing substrates to water relations of transplanted root balls is unknown. Therefore, a field experiment was undertaken to determine water relations of a pine-bark substrate (container removed) within a drying mineral soil over a three week period. A range of common production container sizes—3.7 L (#1), 7.5 L (#2), 21.9 L (#7), 50.6 L (#15), and 104.5 L (#25)—was used. The fraction of substrate volume that is water [total volumetric water (TVW)] within the top and middle zones of substrate was compared to TVW at corresponding depths of adjacent mineral soil. The fraction of substrate and soil volume that is plant-available water [plant-available volumetric water (PAVW)] was calculated by subtracting the fraction of substrate or soil volume below where water is unavailable to most plants (measured with pressure plates) [plant-unavailable volumetric water (PUVW)] from each TVW measurement. The pine-bark substrate had a PUVW of 0.32 compared to a PUVW of 0.06 for soil. Top sections of substrate dried to near zero PAVW 6 days after irrigation for all containers. Larger container sizes maintained higher PAVW in middle sections than smaller container sizes, and PAVW was always higher in the adjacent soil than in the embedded substrate. Overall, very little PAVW is held by the embedded pine-bark growing substrate, suggesting the need for container substrates with greater water retention once transplanted to mineral soils.
Cary L. Rivard, Olha Sydorovych, Suzanne O'Connell, Mary M. Peet, and Frank J. Louws
; Noling and Becker, 1994 ; Sydorovych et al., 2008 ). With the exception of the hydroponic greenhouse industry, few tomato growers in the United States use grafted transplants for fruit production ( Kubota et al., 2008 ). There are two primary assumptions
Yai Ulrich Adegbola, Paul R. Fisher, and Alan W. Hodges
that have lower labor costs for harvesting cuttings), filling trays with substrate, inserting cuttings into the substrate (“transplanting”), moving assembled trays with cuttings to the propagation area, growing the roots and shoots of cuttings, and
Ajay Nair, Mathieu Ngouajio, and John Biernbaum
To optimize the production system, most vegetable crops are established from greenhouse-grown transplants. Transplant production is a critical phase that significantly affects growth and development of the crop in the field ( Dufault, 1998 ). Some