Medium and Fertilizer Affect the Performance of Phalaenopsis Orchids during Two Flowering Cycles

in HortScience
View More View Less
  • 1 Department of Horticultural Sciences, Texas A&M University Agricultural Research and Extension Center, 2415 East Highway 83, Weslaco, TX 78596

Bare-root seedling plants of a white-flowered Phalaenopsis hybrid [P. arnabilis (L.) Blume × P. Mount Kaala `Elegance'] were grown in five potting media under three fertility levels (0.25, 0.5, and 1.0 g·liter-1) from a 20N-8.6P-16.6K soluble fertilizer applied at every irrigation. The five media included 1) 1 perlite:1 Metro Mix 250:1 charcoal (by volume); 2)2 perlite:2 composted pine bark:1 vermiculite; 3) composted pine bark; 4) 3 perlite:3 Metro Mix 250:1 charcoal; and 5) 1 perlite:1 rockwool. During the first flowering season, plants in the 1 perlite: 1 Metro Mix 250:1 charcoal medium had slightly fewer but larger flowers and thicker stalks (section of the inflorescence between the base and oldest flower) than those in the 1 perlite:1 rockwool medium. Medium had no effect on stalk length. Two media (3 perlite: 3 Metro Mix 250: 1 charcoal and 1 perlite: 1 rockwool) resulted in root systems that were inferior to those in the others. Fertilizer level had no effect on bloom date or flower size. Regardless of medium, increasing the fertility from 0.25 to 1.0 g·liter-1 increased flower count, stalk diameter and length, and leaf production following flowering. During the second flowering season, media had limited effect on plant performance. Increased fertility promoted earlier inflorescence emergence and blooming. Higher fertilizer rates also caused a linear increase in the number of flowers and inflorescences per plant, and in stalk diameter, total leaf count, and leaf size.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 46 46 14
PDF Downloads 74 74 24