Influence of Fertilizer Placement on Plant Quality, Root Distribution, and Weed Growth in Container-grown Tropical Ornamental Plants

Abstract

<jats:p>In two experiments, chinese hibiscus (<jats:italic>Hibiscus rosa-sinensis</jats:italic>), bamboo palm (<jats:italic>Chamaedorea seifrizii</jats:italic>), areca palm (<jats:italic>Dypsis lutescens</jats:italic>), fishtail palm (<jats:italic>Caryota mitis</jats:italic>), macarthur palm (<jats:italic>Ptychosperma macarthurii</jats:italic>), shooting star (<jats:italic>Pseuderanthemum laxiflorum</jats:italic>), downy jasmine (<jats:italic>Jasminum multiflorum</jats:italic>), plumbago (<jats:italic>Plumbago auriculata</jats:italic>), alexandra palm (<jats:italic>Archontophoenix alexandrae</jats:italic>), and foxtail palm (<jats:italic>Wodyetia bifurcata</jats:italic>) were transplanted into 6.2-L (2-gal) containers. They were fertilized with Osmocote Plus 15N-3.9P-10K (12-to14-month formulation) (Expt. 1) or Nutricote Total 18N-2.6P-6.7K (type 360) (Expt. 2) applied by either top dressing, substrate incorporation, or layering the fertilizer just below the transplanted root ball. Shoot dry weight, plant color, root dry weights in the upper and lower halves of the root ball, and weed shoot dry weight were determined when each species reached marketable size. Optimal fertilizer placement method varied among the species tested. With the exception of areca palm, none of the species tested grew best with incorporated fertilizer. Root dry weights in the lower half of the root ball for chinese hibiscus, bamboo palm, and downy jasmine were greatest when the fertilizer was layered and root dry weights in the upper half of the root ball were greatest for top-dressed chinese hibiscus. Weed growth was lower in pots receiving layered fertilizer for four of the six palm species tested.</jats:p>

Impact of Container Nursery Production Practices on Weed Growth and Herbicide Performance

“…When fertilizer placement methods were combined with the use of herbicides, (oryzalin + oxyfluorfen or pendimethalin + oxyfluorfen), dibbling resulted in 89% to 99% control compared with 82% to 90% for topdressing and 81% to 98% for incorporation methods across all three weed species. Broschat and Moore (2003) reported similar findings; when examining the impact of fertilizer placement on crop growth, weed biomass was either similar to or less in container-grown palms when fertilizers were layered, or placed below the soil surface, compared with incorporation or topdressed placements.…”

“…), downy jasmine (Jasminum multiflorum Burm F.), plumbago (Plumbago auriculata Lam.) (Broschat and Moore, 2003), gumpo azaleas (Azalea · hybrid 'Gumpo White') (Marble et al, 2012), and several other economically important ornamental species (Altland et al, 2004) compared with topdressing or incorporating at similar rates.…”

Evaluating Fertilization and Water Practices to Minimize NO3-N Leachate from Container-grown Forsythia

“…2, drip-irrigated only, showed that among the CRF placement methods, the calculated amounts of NO 3 -N leached from dibble containers over the duration of the experiment were intermediate for CRF rates (mean, 252 mg/pot; range, 151 to 367 mg/pot) compared with incorporated (mean, 295 mg/pot; range, 151 to 410 mg/ pot) and topdressed (mean, 79 mg/pot; range, 65 to 108 mg/pot). Only a few studies have compared the effectiveness of these three fertilizer placement methods (Altland et al, 2004;Broschat and Klock-Moore, 2003) and no placement methods were pronounced. Responses varied with species, location, and cultural factors (Broschat and Klock-Moore, 2003;Million et al, 2007).…”

“…Only a few studies have compared the effectiveness of these three fertilizer placement methods (Altland et al, 2004;Broschat and Klock-Moore, 2003) and no placement methods were pronounced. Responses varied with species, location, and cultural factors (Broschat and Klock-Moore, 2003;Million et al, 2007). Higher plant growth with dibbled CRF also has been reported by Altland et al (2004) for container-grown azalea (Rhododendron sp.…”

A Review of Weed Control Practices in Landscape Planting Beds: Part I–Nonchemical Weed Control Methods

“…In a container study, Altland et al (2004) reported that dibbling fertilizer (placing fertilizer directly beneath root ball) significantly reduced weed germination compared with incorporating (mixing fertilizer in with media) or top-dressing (placing fertilizer on container media surface). In a similar study, Broschat and Moore (2003) reported less weed growth in container-grown ornamentals when fertilizer was layered just beneath the root ball (a modified dibble) compared with incorporation or topdressing. Few studies investigating the effects of fertilizer placement on weed growth in the landscape have been reported.…”