Bedding plants in a changing climate.

摘要

The effects of growing more than one plant and more than one species of bedding plants (Petunia hybrida cv. Hurrah White and Impatiens cv. Cajun Violet) in one container on the ornamental quality of these plants were studied. Plants grown from plugs in 2-litre containers were irrigated daily under a 25 or 100% watering regime. Plant combinations per container were: one P. hybrida plant (P), one Impatiens plant (I), 2 P. hybrida plants (PP), and one P. hybrida plant with one Impatiens plant (PI). Under the 100% watering regime, P required, on average, approximately 30% more water than I. Adding one plant in the container increased the water requirement by only 5 and 10% for PI and PP, respectively. The 2 watering regimes resulted in different substrate moisture contents from day 5. A decrease in substrate moisture content to around 0.1 m3/m3 (from day 12) under the 25% watering regime reduced plant size and number of flowers in both species. However, plants under this treatment were more efficient in biomass and flower production in relation to the volume of water applied. P. hybrida plants that experienced competition from other plants and reduced watering regime showed enhanced efficiency of flower production. P. hybrida height, dry weight, and number of flowers and buds were also greater under PI than under PP. For Impatiens in the dry regime, plant quality was acceptable under I, but was adversely affected under PI.