The Mediterranean region is recognized as a global biodiversity hotspot. However, over the last decades, the cessation of traditional farming in the north part of the Mediterranean basin has given way to strong afforestation leading to occurrence of abandoned agricultural lands colonized by pioneer expansionist species like
Pinus halepensis
. This pine species is known to synthesize a wide range of secondary metabolites, and previous studies have demonstrated strong allelopathic potentialities of its needle and root leachates.
Pinus halepensis
is also recognized to release significant amounts of volatile organic compounds (VOC) with potential allelopathic effects that have never been investigated. In this context, the objectives of the present study were to improve our knowledge about the VOC released from
P. halepensis
needles and roots, determine if these VOC affect the seed germination and root growth of two herbaceous target species (
Lactuca sativa
and
Linum strictum
), and evaluate if soil microorganisms modulate the potential allelopathic effects of these VOC. Thirty terpenes were detected from both, needle and root emissions with β‐caryophyllene as the major volatile. Numerous terpenes, such as β‐caryophyllene, δ‐terpinene, or α‐pinene, showed higher headspace concentrations according to the gradient green needles < senescent needles < needle litter. Seed germination and root growth of the two target species were mainly reduced in presence of
P. halepensis
VOC. In strong contrast with the trend reported with needle leachates in literature, we observed an increasing inhibitory effect of
P. halepensis
VOC with the progress of needle physiological stages (i.e., green needle < senescent needle < needle litter). Surprisingly, several inhibitory effects observed on filter paper were also found or even amplified when natural soil was used as a substrate, highlighting that soil microorganisms do not necessarily limit the negative effects of VOC released by
P. halepensis
on herbaceous target species.