ABSTRACT

Soil is the living medium where the roots of a tree grow. The first factor to take into account when choosing a soil for citriculture is texture (particle size). There are several schemes to classify soil texture. The easiest way to check if a soil is suitable for a citrus plantation is drainage. A high percentage (more than 60-65 per cent) of small-sized particles avoids percolation. Water must never flood either the surface or the root explored layer. Water accumulation discourages aeration and creates conditions for asphyxia. Rootstocks react differently to asphyxia, but even the most tolerant ones (Poncirus and its relatives) are severely affected by long-term flooding. The best conditions for water infiltration are found in sandy soils although they dry quickly and need frequent watering. Indeed, soil compaction does not depend only on particle size. Cementation at various depths (hardpan) or on the surface may occur for several reasons, including human and mechanical traffic.