and at the same time the maintenance of quality of the plants produced. This can be achieved by increasing the plant density per area or by growing plants in smaller pots. The influence of pot size on growth and development depends on the species and
Smiljana Goreta, Kristina Batelja, and Slavko Perica
Anne K. Carter
In the northeastern United States, vegetable crop classes and growers' meetings are often held during winter months when field demonstrations are impossible. A pot-sized demonstration was set up in the greenhouse in May and Nov. 2002 as a student laboratory to show the effects of season extension materials on the early growth of winter squash. The treatments were black plastic mulch and rowcover, alone and in combination. The treatments were also placed on either a heated [18.3 °C (65 °F)] or unheated germination mat to simulate warmer and cooler spring soils. Butternut squash (Cucurbita moschata) was sown in 10.2 × 10.2 × 11.43-cm (4 × 4 × 4.5 inches) pots in soilless medium. The plants were grown and observed for 30 days, then harvested and weighed. The plants in the greenhouse grew as expected of plants grown under similar conditions in the field. Bottom heat, mulch, and rowcover had an increasingly greater effect on the growth of subsequent leaves as shown by comparisons of leaves 1, 2, and 3. Warmer soils tended to have the greatest effect on all measured parameters, but this was not as obvious in the May experiment as it was in the November experiment. Thus, this pot demonstration can be used in a student laboratory. The pots and plants are small enough to transport to and set up at winter growers' meetings as well.
Myung Min Oh, Young Yeol Cho, Kee Sung Kim, and Jung Eek Son
maintained by replenishing water every 30 min. Determination of water contents in different pot sizes. Three pot sizes (diameter/height: 6 cm/6.3 cm, 10 cm/9.0 cm, and 15 cm/13.5) were placed under four different irrigation systems: NFW (5×; five irrigations
D. Scott NeSmith and John R. Duval
Transplants for both vegetable and floral crops are produced in a number of various sized containers or cells. Varying container size alters the rooting volume of the plants, which can greatly affect plant growth. Container size is important to transplant producers as they seek to optimize production space. Transplant consumers are interested in container size as it relates to optimum post-transplant performance. The following is a comprehensive review of literature on container size, root restriction, and plant growth, along with suggestions for future research and concern.
Geno A. Picchioni, Jagtar Singh, John G. Mexal, and Ryan M. Goss
respectively. The plants were organized by pot size and species into four blocks and placed atop wooden pallets at the FGSC. The outer perimeters of the 5 × 5-pot 5-gal-size blocks and 6 × 6-pot 1-gal-size blocks were not included in data collection and
Kaitlyn M. McBride, Richard J. Henny, Terri A. Mellich, and Jianjun Chen
correlation analyses. Results Soluble salts of root-zone solutions measured by a conductivity meter increased curvilinearly with the increased rates of fertilizer regardless of pot size (data not shown). For example, as the rate increased, mean soluble salt
Jeff S. Kuehny, Matt Taylor, and Michael R. Evans
about a 60% lower root dry weight in paper vs. plastic containers. Results for R:S ratio of geraniums were similar or mixed for all pot sizes, types, and locations. However, the R:S ratio was higher for impatiens grown in peat and CowPots containers than
Jeff L. Main, Paul G. Thompson, and William B. Burdine Jr.
Seedling plants from the three parents `Resisto', `Southern Delight', and `L86-33', along with three pot sizes (3.8-, 10.2-, and 17.7-cm diameters) were evaluated. Root characteristics evaluated in both the greenhouse and field included: number, length, diameter, length diameter ratio (L:D), size, skin color, flesh color, internal cambium ring (color and width), and the number of lateral and secondary roots. After greenhouse evaluation, plants were transplanted to the field. The 3.8-cm pot did not produce enough roots in the greenhouse for evaluation. In the 10.2-cm pots, greenhouse root number was correlated with the yield, root size, and L:D, and negatively correlated with skin color in the field. Flesh color was correlated with smoothness and flesh color in the field. In the 17.8-cm pots, flesh color, smoothness, and skin color in the greenhouse were correlated with the same character in the field. Skin color was also negatively correlated with smoothness in the field. No differences were found in field yield due to pot size. Results from one season showed that the 10.2-cm pot was effective for greenhouse selection of flesh color, skin color, and smoothness in seedling sweetpotato plants.
Marc van Iersel
Salvia splendens `Top burgundy' was grown in pots of different sizes (5, 50, 150, and 450 mL) to assess the effect of rooting volume on the growth and development of salvia. Seeds were planted in a peat-lite growing medium and plants grown in a greenhouse during the winter and spring of 1996. Plants were spaced far enough apart to minimize mutual shading and interplant light competition. Plants were harvested at weekly intervals and shoot and root dry mass and leaf area were measured. Relative growth rate (RGR) and net assimilation rate were calculated from these data. Differences in plant size became evident at 25 days after seeding. A small pot size (5 mL) decreased root and shoot dry mass, RGR, and NAR, while increasing the root:shoot ratio. Differences between the pot sizes became more apparent during the course of the experiment. The observation that root: shoot ratio decreased with increasing pot volume suggests that the decreased plant size in smaller pots was not the direct effect of reduced root size. Growth most likely was limited by the ability of the roots to supply the shoots with sufficient water and/or nutrients. Pot volume did not only affect the growth, but also the development of the plants. Salvia flowered faster in bigger pots (about 50 days after seeding in 450-mL pots), while the plants in 5-mL cells did not flower during the 9-week period of the experiment.
Shravan K. Dasoju and Brian E. Whipker
Drench applications of plant growth retardant paclobutrazol were applied at 2, 4, 8, 16, or 32 mg a.i./pot, plus an untreated control to pot sunflowers (Helianthus annuus cv. `Pacino') to determine its effect as a chemical height control. All paclobutrazol concentrations applied significantly reduced plant height by »27% when compared to the untreated control, but excessively short plants were observed at 16 and 32 mg a.i./pot. Plant diameter was also significantly decreased by »16% at 2 and 4 mg a.i./pot of paclobutrazol, when compared to the untreated control. Flower diameter decreased by »4% at 2 and 4 mg a.i./pot of paclobutrazol, but only concentrations ≥4 mg a.i./pot were significantly different from the untreated control. Paclobutrazol concentrations had no effect on days from potting to flowering. Drench concentrations of 2 and 4 mg a.i./pot of paclobutrozol produced optimum height control in relation to 16.5-cm-diameter pot size used.