Location: Horticultural Crops Research UnitTitle: Effect of nitrogen rate and irrigation frequency on plant growth and nutrient uptake of container-grown Hydrangea macrophylla ‘Merritt’s Supreme’
|LI, TONGYIN - Mississippi State University|
|BI, GUIHONG - Mississippi State University|
|HARKESS, RICHARD - Mississippi State University|
|DENNY, GEOFFREY - University Of Florida|
Submitted to: Southern Nursery Association Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 7/15/2014
Publication Date: 9/1/2014
Citation: Li, T., Bi, G., Scagel, C.F., Harkess, R.L., Denny, G.C. 2014. Effect of nitrogen rate and irrigation frequency on plant growth and nutrient uptake of container-grown Hydrangea macrophylla ‘Merritt’s Supreme’. In: Southern Nursery Association Conference, July 21-23, 2014, Atlanta Georgia. 59:32-36.
Technical Abstract: The production of high quality container-grown nursery plants requires adequate but not excessive nutrients and water during production. Given the knowledge that N is the most important nutrient element for plant growth and that it is often the limiting factor, nursery growers tend to apply high levels of N fertilizer to avoid potential N deficiency. However, over-fertilization can be detrimental to plant growth due to potential salt accumulation under water shortage, or cause considerable loss of nutrients and environmental issues due to excessive irrigation . Nutrient availability to plant roots in response to different N rates and irrigation frequency conditions has not been well clarified for hydrangea. The objective of this study was to investigate the effect of N rate and irrigation frequency on plant growth and nutrient uptake of container-grown Hydrangea macrophylla ‘Merritt’s Supreme’. Plants were grown for 4 months with 4 rates of N fertilizer and irrigated at two different frequencies. Plants in both irrigation treatments received the same amount of water each day in either one application or split applications in the morning and afternoon. Plant growth, daily water use, nutrient uptake, photosynthesis and stomatal conductance were measured at several times during the experiment. Irrigation did not influence growth, leaf color, N uptake or photosynthesis, suggesting irrigation frequency did not result in a difference in water availability to hydrangea plants. Without being exposed to significantly different water stress induced by the two irrigation frequencies, plant N uptake did not appear to be limited by substrate water availability. N was the primary factor affecting growth. Results of this study indicated that 210 ppm nitrogen (N) is sufficient for the production of hydrangea plants considering no difference in plant growth (PGI, dry weights, N content, photosynthetic performance) was found between plants fertilized with 210 ppm and 280 ppm N.