INFLUENCE OF PINCHING, SOME FERTILIZATION TREATMENTS AND SPRAYING WITH ALAR ON SOLIDAGO PLANTS. B. FLOWERING CHARACTERISTICS

This study was carried out at Dept. of Ornamental Hort., Fac. Agric., Cairo Univ. and the applied part was carried out under open field conditions at the Experimental Farm of Hort. Res. Inst., ARC, Giza, Egypt during 2015 and 2016 seasons to investigate the effect of pinching, bio- and chemical fertilization (as a soil drench), foliar spraying with alar and their interactions on flowering parameters of goldenrod (Solidago hybrida, "Tara") with the aim of producing high quality plants appropriate to be used as flowering pot plants. Flowering stem length (cm), flowering start date (days), flowering stem fresh and dry weights (g) and number of flowering branches were greatly affected by single, double and triple treatments applied in this study. Regarding the effect of interaction treatments between pinching, fertilization and alar, non-pinching in addition to bio-fertilization + NPK at 3 g/pot + alar at 1000 ppm resulted in the longest flowering stems. Non-pinching in addition to bio-fertilization + NPK at 1.5 g/pot + alar at 500 ppm shared some other treatments (i.e. pinching in addition to bio-fertilization + NPK at 3 g/pot + alar at 500 ppm) and resulted in the lowest flowering start date values. On the other hand, pinching in addition to bio-fertilization + NPK at either 1.5 or 3 g/pot + alar at 500 ppm produced the heaviest fresh flowering stems and to some extent the highest number of flowering branches. However, non-pinching in addition to alar at 1000 ppm + NPK at 3 g/pot either with or without bio-fertilization resulted in the heaviest flowering stems dry weight. According to the previous findings and from an aesthetic point of view, it is recommended to treat goldenrod transplants grown in 14 cm pots with pinching in addition to bio-fertilization plus NPK at either 1.5 or 3 g/pot + spraying with alar at 500 ppm to produce high quality goldenrod plants appropriate to be used as flowering pot plants.