Why Agroforestry Systems Need Ground Cover
Agroforestry is the backbone of smallholder agriculture in the Philippines. Millions of hectares are planted in multi-crop systems: coconut with cacao understory, coconut with coffee, coconut with banana, or coconut with fruit trees. These diversified systems spread economic risk and increase per-hectare income compared to monoculture.
But the ground layer in most Philippine agroforestry systems is neglected. Between the tree crops, the soil is either bare (eroding and losing fertility) or dominated by unproductive grasses and weeds that compete with crop roots for water and nutrients. This is where cover crops transform the economics of agroforestry.
Leguminous cover crops planted between tree rows fix atmospheric nitrogen into the soil, suppress weeds without herbicide, prevent erosion during heavy rains, and build soil organic matter that improves water retention during dry periods. In a multi-crop system, these benefits compound because every crop in the system shares the improved soil conditions.
Cover Crops in Coconut + Cacao Systems
The coconut-cacao intercropping model is one of the most promoted agroforestry systems in the Philippines, supported by government programmes and industry organisations. Coconut provides the upper canopy while cacao grows in the partial shade beneath.
In this system, cover crops occupy the ground layer between cacao rows and around coconut trunks. The shade dynamics are critical: mature coconut + cacao systems can produce 50 to 70% shade at ground level, which limits species selection to shade-tolerant varieties.
Recommended species: Centrosema pubescens (CP) is the best fit for coconut-cacao systems because it tolerates heavy shade and persists under closed canopy. Supplement with Pueraria javanica (PJ) in areas with more light penetration, such as along farm edges and access paths.
Avoid Mucuna bracteata in cacao systems. MB's aggressive climbing habit can smother young cacao trees if not managed carefully, and the management labour required offsets the ground cover benefits.
Cover Crops in Coconut + Coffee Systems
Coffee intercropped with coconut follows a similar shade model to cacao but with some differences in ground management. Coffee has a shallower root system than cacao and is more sensitive to root competition, so cover crop species must be chosen to minimise below-ground competition.
Recommended species: A light-density planting of CP + Calopogonium caeruleum (CC) provides ground cover without the aggressive root competition that denser PJ plantings might create. Keep cover crops trimmed back from the drip line of coffee plants during the flowering and fruiting period to reduce moisture competition.
The nitrogen fixed by leguminous cover crops is particularly valuable in coffee systems. Coffee has high nitrogen demand during vegetative growth, and the slow release of nitrogen from decomposing cover crop material provides a steady, low-cost nitrogen source that reduces the need for synthetic urea applications.
Cover Crops in Coconut + Banana Systems
Banana intercropped with coconut is common in Visayas and Mindanao. Banana's large leaves create additional shade at ground level, and banana plantations generate significant organic waste (pseudostems, leaves) that decomposes on the soil surface.
Cover crops in banana systems serve a specific purpose beyond general ground cover: supporting soil resilience. Banana production in the Philippines faces the serious challenge of Fusarium TR4 (Panama disease), which spreads through contaminated soil. Research suggests that biologically active soil with diverse microbial communities is associated with lower Fusarium activity and may support resilience as part of an integrated approach.
Recommended approach: Establish PJ + CP ground cover between banana rows and apply SoilBoost EA to boost soil microbial diversity. The combination of living root exudates from cover crops and the humic acid in SoilBoost EA supports a more biologically active, competitive soil environment, which research associates with greater resilience to Fusarium pressure.
Practical Integration Tips
Planting Layout
In agroforestry systems, cover crops are planted in the inter-row spaces between tree crops. Maintain a clear zone of 50 to 75 cm around the base of each tree crop to prevent direct competition. This clear zone can be maintained by occasional manual trimming rather than herbicide application.
Managing Cover Crop Vigour
In fertile soils, cover crops can become overly vigorous and begin climbing tree crops. Regular monitoring and trimming of climbing growth is essential, particularly for PJ which tends to climb if not managed. In mature agroforestry systems with heavy shade, climbing is naturally suppressed because the cover crop lacks the energy for vertical growth.
Integrating with Organic Waste
Agroforestry systems generate organic waste: coconut husks, cacao pod shells, banana pseudostems, coffee pulp. Rather than removing this waste, distribute it on the soil surface between cover crop rows. The combination of living cover crop roots and decomposing organic matter creates ideal conditions for building soil organic carbon and supporting earthworm populations.
Economic Benefits for Smallholders
For Philippine smallholders operating 1 to 5 hectare agroforestry plots, cover crops deliver economic benefits across every crop in the system simultaneously. The nitrogen fixation reduces fertiliser purchases for all tree crops. The weed suppression eliminates or reduces herbicide costs. The erosion control preserves the topsoil that all crops depend on. And the moisture retention during dry periods reduces drought stress across the entire system.
These benefits compound with SoilBoost EA application, which accelerates the soil biological improvements that cover crops initiate. The combined investment in cover crop seeds plus SoilBoost EA typically pays for itself within 18 months through reduced input costs and improved crop performance.
Getting Started with Agroforestry Cover Crops
Start by assessing the shade level in your agroforestry system. This determines which species to plant. For heavy shade (coconut + cacao, mature coconut + coffee), prioritise CP. For moderate shade (young plantings, coconut + banana), use a PJ + CP blend. For light shade (widely spaced coconut), the full PJ + CM + CP mix works well.
Browse our cover crop seed collection or contact us on WhatsApp to discuss the right species mix for your agroforestry system.
Related Resources
- 5-Species Cover Crop Comparison
- Best Cover Crop for Oil Palm
- SoilBoost EA for Durian and Fruit Trees
- Frequently Asked Questions
Frequently Asked Questions
Which cover crop species is best for shaded coconut-cacao agroforestry systems?
Centrosema pubescens (CP) is the best cover crop for coconut-cacao systems because it tolerates the 50-70% shade that mature coconut-cacao canopies produce. Supplement with Pueraria javanica (PJ) along farm edges and access paths where more light penetrates. Avoid Mucuna bracteata in cacao systems as its aggressive climbing habit can smother young cacao trees.
How do cover crops fit into managing Panama disease (Fusarium TR4) pressure in Philippine banana plantations?
Research suggests that biologically active soil with diverse microbial communities is associated with lower Fusarium activity. Establishing PJ + CP ground cover between banana rows and applying SoilBoost EA to support soil biological activity helps build a more competitive soil environment that research associates with greater resilience to Fusarium pressure. Cover crops and SoilBoost EA are not a cure or a disease treatment; they may support soil health as one part of an integrated management approach that must follow agronomist, quarantine, and resistant-variety guidance.
How should cover crops be managed around tree crop bases in agroforestry?
Maintain a clear zone of 50 to 75 cm around the base of each tree crop to prevent direct competition for water and nutrients. This clear zone is maintained by occasional manual trimming rather than herbicide application. Monitor for climbing growth, particularly with PJ, and trim any vines that begin ascending tree trunks.
What economic benefits do cover crops provide to Philippine smallholder agroforestry farms?
Cover crops deliver benefits across every crop in the system simultaneously: nitrogen fixation reduces fertiliser purchases, weed suppression eliminates or reduces herbicide costs, erosion control preserves productive topsoil, and moisture retention reduces drought stress. The combined investment in cover crop seeds plus SoilBoost EA typically pays for itself within 18 months through reduced input costs and improved crop performance.
SoilBoost EA is a soil conditioner and our cover crops are seeds. They are not fungicides, pesticides, plant protection products, or standalone treatments for Fusarium TR4, Panama disease, Phytophthora, or any crop disease. They may support soil health and root-zone conditions as part of a broader agronomy program, but disease management must follow local agronomist, regulatory, sanitation, drainage, and resistant-variety guidance.
