INFLUENCE OF AGE AT TRANSPLANTING AND INTRA-ROW SPACING ON GROWTH AND AESTHETIC CHARACTERISTICS OF SOME FOUNDATION PLANTS IN THE LANDSCAPE

Abstract

ABSTRACT Foundation plants are important natural elements of visual landscapes. Understanding responses of different foundation plants to transplanting age and plant spacing is crucial for landscape development. The study was conducted to evaluate propagation, growth and aesthetic attributes of three plant species under different intra-row spacings and transplanting ages in the nursery and on the landscape of the Federal University of Agriculture, Abeokuta (Latitude 7°15’N and Longitude 3° 25’E) in 2022 and 2023. Propagation of Duranta repens (Yellow bush), Buxus sempervirens (West indies) and Ixora coccinea (Jungle flame) was evaluated in experiment I. Stem cuttings of these plants were raised in the nursery in polyethylene pots filled with topsoil. Experiment II investigated the growth and aesthetic performance of the three plant species in the field under 25, 50 and 75 cm intra-row spacings and ages of 8, 10 and 12 weeks old at transplanting. Treatments in both Experiments I and II were laid out in Completely Randomized Design with three replicates. Data were collected on percentage rooted cuttings, percentage survival, number of leaves, plant height, number of branches, canopy spread, shoot fresh, shoot dry weights and aesthetic impression. Data collected were subjected to Analysis of Variance and significant treatment means were separated using Least Significant Difference at 5% probability level. Results showed that there was no significant difference (p≥0.05) in percentage rooted and sprouted cutting among the three plant species. However, at 10 weeks after planting B. sempervirens had the tallest (17.23 cm) ramet with highest number of leaves/plant (123) and branches (9 branches/plant). Age at transplanting and spacing significantly affected percentage survival, number of leaves, plant height, number of branches, canopy spread, shoot fresh and dry weights, colour and form among the three plant species evaluated. Buxus sempervirens ramet transplantedat 10 weeks old using 25 cm intra-row spacingshortest period (180 days). Duranta repens ranked highest in terms of colour attractiveness while B. sempervirens performed better with form using visual assessment ranking. Canopy formation covering an area 1350 cm was in the order of B. sempervirens>D. repens>I. coccinea. Optimum growth and aesthetic characteristics in B. sempervirens and D. repens occurred when 10 weeks old ramets were transplanted at 50 cm intra-row spacing, and I. coccinea, when 12 weeks old ramet were transplanted at 25 cm intra-row spacing. The study concluded that B. sempervirens, D. repens and I. coccinea are suitable for use as foundation plants.