(95) Black-eyed Susan (Rudbeckia hirta L.) as a Potted Plant Crop in Response to Pinching and Paclobutrazol

Abstract

<jats:p>In two experiments, seedlings of black-eyed susan were transplanted into 15-cm pots and after 1 week received one of the following treatments: media drench application of 0.1, 1, 10, or 100 mg·L<jats:sup>-1</jats:sup> of paclobutrazol or pinching back of terminal growth once, twice, or three times. After plants reached salable size, plant height, lateral branch length and number, and flower counts were taken, and plants were harvested for dry weights. In the first experiment, all pinching treatments and 10 mg·L<jats:sup>-1</jats:sup> paclobutrazol reduced plant height and increased lateral branching. Flower count at harvest was enhanced by paclobutrazol and reduced by pinching, due to delayed development of inflorescences. Lateral branching and flower bud count were greatest in the second study on plants receiving three pinches. The 100 mg·L<jats:sup>-1</jats:sup> paclobutrazol-drenched plants had lowest height, dry weight, and bud count and were severely stunted. The most attractive plants appeared to be those that received the 10 mg·L<jats:sup>-1</jats:sup> paclobutrazol drench treatments.</jats:p>