Plantain

Plantain: a species with high agroecological functionality in Mediterranean agricultural systems

In Mediterranean agricultural systems, increasingly exposed to water stress, soil compaction, and fertility loss, the agroecological transition requires a real paradigm shift.
It’s not simply a matter of introducing new products or technologies, with the risk of “substitution” agriculture, switching from one input to another, but of rethinking the role of wild species already present in agroecosystems, recognizing them as strategic resources for soil and functional biodiversity.
In this short article, we will focus on wild plantain species, belonging to the Plantago genus.
Plants commonly perceived as weeds, when observed from an agroecological perspective, reveal themselves to be highly functional species, capable of providing measurable and manageable ecosystem services.

A seemingly “trivial” plant
Walking along a path or at the edge of a cultivated field, plantain (Plantago spp.) is almost always present.
Resistant to trampling, tolerant of agricultural vehicles, and capable of growing where other species fail, it is often dismissed as a mere weed.
Yet, these very characteristics tell a different story.
In an era marked by the use of heavy agricultural machinery, soil compaction, biodiversity loss, and water stress, plantain represents an emblematic example of how a spontaneous species can assume a central role in Mediterranean agricultural systems, when viewed from an agroecological perspective.

What does its presence on the farm mean?
From an agronomic perspective, plantain is not a “neutral” species.
Its presence often signals imbalances related to the physical aspects of the soil, such as compaction and excessive use of mechanical equipment, and chemical imbalances, particularly related to nitrogen availability.
In this sense, one of the most widespread species of the Plantago genus, Plantago major, represents a true bioindicator species, useful for guiding technicians and farmers towards more informed management choices.

Plantain as a Bioindicator
When we observe a dominance of Plantago major in spontaneous vegetation, we can say, with a good approximation, that we are dealing with:
– highly compacted soils;
– high concentration of available nitrogen;
– moist soils, with poor structure and limited drainage.
Before eliminating it, the question to ask should be:
What is the system signaling to us through the presence of this plant?

From Control to Management: Plantain from an Agroecological Perspective
In a conventional approach, plantain is often the subject of mechanical or chemical control.
In agroecology, however, we move from control to management.
The first step is to ask whether this species can perform a useful function within the farm system.
In light of scientific evidence, the answer is clearly yes.
The Plantago genus can, in fact, contribute to:
– improving the physical stability of the sward;
– supporting functional biodiversity;
– regulating nitrogen processes;
– produce biomass rich in secondary metabolites;
– accumulate and biotransform heavy metals.
Plantago seeds, known as psyllium, are also characterized by a high content of hydrophilic polysaccharides (mucilage), capable of absorbing large amounts of water and forming viscous gels, with significant effects on soil water dynamics.

Plantago spp. as a Nature-Based Solution: Scientific Evidence
Numerous studies on Plantago lanceolata demonstrate a slowdown in nitrification processes in grazing systems or systems characterized by organic inputs with an unbalanced C/N ratio (Simon et al., 2019; Peterson et al., 2022).
Nitrification is an aerobic process that transforms ammoniacal nitrogen into nitrate, a form easily absorbed by plants.
While this represents an agronomic advantage, nitrate is highly mobile in the soil and, if not promptly intercepted by the roots, can be lost through leaching or in gaseous form.
Plantago lanceolata is capable of activating biological inhibition mechanisms of nitrification, mediated by secondary metabolites such as aucubin (Gardiner et al., 2020).
For this reason, plantain can be considered a true Nature-Based Solution (NBS) for improving nitrogen efficiency in vulnerable agricultural systems.
Cover crops have also been shown to increase biodiversity in Mediterranean orchards compared to bare soil (de Pedro et al., 2020).
Thanks to their hardiness, Plantago spp. contributes to plant cover in the most stressed areas, improving sward stability.
Extracts of Plantago lagopus and P. major have shown:
– antifungal activity against soil-borne pathogens (Rhizoctonia solani, Fusarium spp.);
– induction of acquired systemic resistance;
– dose-dependent phytotoxicity in tomato, requiring caution and rigorous protocols (Behiry et al., 2022; Lam-Gutiérrez et al., 2025).

Use in Mediterranean cropping systems
Olive grove
– more resilient cover crops;
– Reduced erosion and improved soil conservation;
– Indirect support for functional biodiversity.

Vineyard
– Soil stabilization in work areas;
– Reduction of tillage;
– Buffering function within multifunctional mixes.

Vegetables
– Support for low-input pest management strategies;
– Integration into functional borders;
– Improved efficiency of organic nitrogen sources;
– Mitigation of nitrate emissions into the atmosphere;
– Alignment with agri-environmental policies.

Key Management Rules
– Avoid unwanted spread;
– Use only uncontaminated biomass for extracts;
– Introduce Plantago for specific agroecological functions;
– Always measure the effects on soil, biodiversity, and nitrogen.
The value of plantain emerges only when inserted into a systemic vision of the agroecosystem.

Conclusions
Plantain is a prime example of how a species once considered marginal or a weed can become a strategic lever in the agroecological transition.
A bioindicator of nitrate nitrogen, a soil stabilizer, a modulator of the C/N ratio, and a source of bioactives, Plantago spp. displays a rare multifunctionality, particularly suited to Mediterranean agricultural systems.
The real breakthrough lies not in “letting it grow,” but in consciously designing its role within the agroecosystem.

Francesco Di Lorenzo
Agronomist

To learn more:
– Simon et al., Science of the Total Environment (2019) – https://doi.org/10.1016/j.scitotenv.2019.07.141
– Peterson et al., Biology and Fertility of Soils (2022) – https://doi.org/10.1007/s00374-021-01573-1
– Lavelle et al., Applied Soil Ecology (2006) – https://doi.org/10.1016/j.apsoil.2006.05.001
– Baveye et al., Geoderma (2016) – https://doi.org/10.1016/j.geoderma.2016.07.010

Photo source:
– https://inaturalist-open-data.s3.amazonaws.com/photos/464676873/original.jpg