Effects of mulch on soil pH and the growth of vanilla plants

Abstract

Agroforestry produces various types of waste that can lower soil pH, increase the negative effect of allelochemicals and inhibit the growth of vanilla plants. Studies were conducted to examine the short-term effect (43 to 85 days) of dry and fresh mulches, compost and charcoal on soil pH and the growth of vanilla plants. Studies were performed in an agroforest and in a greenhouse using a completely randomised experimental design. The studies found that during rainy season in the agroforest, the addition of fresh grass clippings decreased soil pH by 0.15 relative control. In contrast, the same addition increased soil pH in greenhouse experiments by 0.22. The addition of compost also decreased soil pH in agroforestry by 0.15 but increased pH in greenhouse by 0.20. A similar effect was also found after the addition of charcoal. The addition of coconut husks and leaf litter in agroforest led to similar soil pH as the control, at 6.0 and 6.42 for coconut husks and leaf litter, respectively. High growth of vanilla plants occurred in a soil pH range from 6.0 to 6.5, irrespective of mulch materials added. This study indicates that environmental conditions change soil-mulch interactions, and that vanilla plants thrive well in soil pH ranging from 6.0 to 6.5 in most of the mulch types tested. leaf (control); CofC- Coffea leaf-compost; CofCh- Coffea leaf-charcoal; G-grass clipping, G0- Gliricidia (control); GC- Gliricidia -compost; GCh- Gliricidia -charcoal; GCH-grass clipping-coconut husk; Int. 1-internode 1, Int. 2-internode 2, etc.; OCCh-leaf litter without compost and charcoal; OCChM-without compost, charcoal and mixed leaf litter; TS0-topsoil (control): Exp-experiment. TSC-topsoil-compost; TSCh-topsoil-charcoal.

PDF adipura_16_1_2022_103_112.pdf

Study Snapshot

Vanilla plants thrive well in soil pH ranging from 6.0 to 6.5, regardless of the mulch materials added, with environmental conditions affecting soil-mulch interactions.

Population: Vanilla plants grown in agroforest and greenhouse conditions

Methods: Controlled experimental study

Outcomes: Soil pH, vanilla plant growth

Results: Vanilla plant growth was highest at soil pH 6.0–6.5, regardless of mulch type.