Coreopsis verticillata ‘Moonbeam’ and Rudbeckia fulgida ‘Goldsturm’ were sprayed with tank mixes of B-Nine and Cycocel in all combinations of 0, 2500, 5000 or 7500 ppm B-Nine and 0, 1000, 1500 or 2000 ppm Cycocel. B-Nine was more effective in controlling height of both cultivars than Cycocel or B-Nine/Cycocel tank mixes. B-Nine alone suppressed height of coreopsis 26-52% (over all concentrations and all data collection dates), in contrast to a 17–41% height suppression when B-Nine was combined with Cycocel. Cycocel alone suppressed height of coreopsis 6–16% over all concentrations and data collection dates. B-Nine suppressed height of rudbeckia 20–40% over all data collection dates, while Cycocel suppressed height of rudbeckia only in the last two weeks of data collection (10 and 12% at weeks 8 and 9, respectively). Tank mixes applied to rudbeckia were not as effective as B-Nine alone for height suppression. Flowering of coreopsis was delayed 6 days by B-Nine and 12–14 days by tank mixes of B-Nine and Cycocel; Cycocel accelerated flowering up to 5 days when used alone. Flowering of rudbeckia was delayed up to 9 days with increasing B-Nine concentrations but was unaffected by Cycocel alone or tank mixes of B-Nine/Cycocel. No phytotoxicity was observed at the concentrations used.

In 2000 and 2004, cultivars of Hemerocallis were treated with foliar applications of 2500 or 5000 ppm benzyladenine (BA) for 1, 2, 3, 4 or 5 consecutive weeks. In both years, BA increased ramet production of all cultivars although treatment response was cultivar dependent. In 2000, an increasing number of BA applications resulted in ‘Lavinia Love’ and ‘Beguine’ forming 1.6 to 3.2 and 0.7 to 1.1 more ramets, respectively, than control plants at 9 weeks after initial treatment (WAT), regardless of concentration. Increasing BA concentration increased ramet formation by up to one ramet in ‘Beguine’ and up to 3 ramets in ‘Lavinia Love’ at 9 WAT, regardless of the number of applications. At 9 WAT in 2004, increasing weekly applications of BA increased ramet formation in ‘Dainty Deb’ from a mean of 1.3 ramets with one application to a mean of 3.0 ramets with five applications, and in ‘Sarah Sikes hybrid’ from 0.5 ramets with one application to 2.1 ramets with five applications, regardless of concentration. Compared to control plants, ‘Dainty Deb’ increased ramet production by 1.9 ramets and 2.3 ramets at 9 WAT in 2004 when treated with 2500 ppm and 5000 ppm BA, respectively, regardless of the number of applications. Compared to untreated controls, ‘Sarah Sikes hybrid’ formed 1.1 and 1.3 more ramets when treated with 2500 ppm and 5000 ppm BA, respectively.

Hosta plantaginea and 11 selections with H. plantaginea parentage were chilled at 4C (39F) for 0, 1, 2, 3, or 4 weeks to determine the effect of chilling duration on subsequent plant growth. At 6 and 12 weeks after chilling treatment (WAT), response to chilling duration was selection dependent with three trends evident. At 6 WAT, eight of the 12 selections showed a decrease in new leaf formation with one or two weeks of chilling, but an increase in new leaf formation with additional chilling. In three of the 12 selections, new leaf formation increased linearly with increased chilling. New leaf formation of H. plantaginea ‘Grandiflora’ was not affected by chilling duration at 6 or 12 WAT. At 12 WAT, growth response of four of the 12 selections changed quadratically with increased chilling, similar to the response at 6 WAT, while leaf formation in seven of the 12 selections increased linearly with increasing chilling duration. At 18 WAT, leaf counts increased linearly in all H. plantaginea selections with increasing chilling duration, demonstrating increased vigor. All selections showed increases in new leaf formation over the 18-week period following chilling, demonstrating that chilling, though beneficial, was not required, and in the short-term, the response to chilling was selection dependent.