Cover crop seeds FAQ

Nitrogen fixation varies significantly by species. PJ fixes up to 250 kg N/ha/year at full ground cover, with 85-93% derived from the atmosphere. MB delivers 150-200 kg N/ha/year (67-84% atmospheric, confirmed by MPOB isotope tracing). CP fixes up to ~293 kg N/ha biomass-N in Philippine field studies and sustains fixation under shade. CM contributes up to ~154 kg N/ha biomass-N (Philippine study). CC contributes up to ~90 kg N/ha equivalent under shade.

Learn more: 5-Species Comparison Guide | Evidence Hub

MB produces up to 28 t/ha/year in open conditions and ~13 t/ha/year under shade (MPOB). PJ produces 8-12 t/ha/year. CM: 6-10 t/ha/year. CP: 5-9 t/ha/year. CC: 3-7 t/ha/year. All species provide excellent organic matter return and nutrient cycling for plantation soils.

Learn more: Compare All 5 Species

CM establishes quickest among seedable species, producing dense cover rapidly after sowing. PJ is also fast-growing with vigorous establishment under full sun. MB achieves 100% ground cover within 6 months, the fastest canopy closure once established, though initial growth is slow for 8-10 months. CP forms dense cover within 4-8 months under adequate rainfall, but requires good conditions during establishment. CC is the slowest at 20 months to complete cover, but persists in the heaviest shade. Ranking by establishment speed: CM > PJ > MB > CP > CC.

Learn more: Full Species Comparison | Seed Calculator

CC tolerates pH as low as 4.0, the most acid-tolerant species. CM prefers pH 4.5-5.0 and high aluminium soils; its nitrogen fixation actually performs better under acidic conditions and declines at neutral pH. PJ tolerates pH 4.5-6.5 including acidic heavy clay. CP and MB adapt across a broader range of pH 4.5-7.0.

Learn more: Species Comparison Guide

PJ contributes 133 kg N, 11 kg P, 110 kg K, 13 kg Ca, and 21 kg Mg per hectare. MB litter contains over 3% N, 0.2-0.3% P, and 2-3% K. Cover crops improve soil structure, reduce bulk density, and increase water infiltration.

Learn more: SoilBoost EA Soil Conditioner | Field Observations

Cover crops promote Rhizobia bacteria and arbuscular mycorrhizal fungi (AMF) associations. They increase soil enzyme activities, support decomposer microbe populations, and improve the soil food web. Some species also suppress soil pathogens and nematodes.

Learn more: SoilBoost EA Field Observations | Soil Enhancer vs Fertilizer

PJ has excellent drought tolerance with 2 m deep roots surviving 5-7 month dry seasons. CC tolerates lower rainfall (700 mm). MB survives dry periods of approximately 4 months once established. CP is moderate, handling 3-4 month dry seasons. CM has poor drought tolerance but re-establishes from its seed bank.

MB provides the highest erosion control with 2-3 m deep pseudo tap roots and rapid dense cover. PJ is excellent, field research confirms 88% runoff reduction and 98% soil loss reduction versus bare soil in replanted rubber. CM and CP provide good control. CC is moderate. Ranking: MB > PJ > CM = CP > CC. Best suited for steep slopes and challenging terrain.

Learn more: PJ vs MB Comparison

CC has the strongest shade tolerance, thriving in up to 90% shade, exceptional under mature cacao and rubber canopies. CP persists under up to 80% shade, yielding approximately 80% of its optimal output. CM is moderately shade tolerant, productive at 40-60% shade, but is the first to be shaded out in species mixtures. PJ tolerates partial shade (moderate). MB requires good light and performs best under open or immature canopies. Shade ranking: CC > CP > CM > PJ > MB.

Learn more: Full Species Comparison

Deep root systems provide drought resilience. Biomass and soil organic matter sequester carbon. Improved soil health buffers against climate variability. Enhanced water infiltration reduces damage from intense rainfall events.

Cover crops reduce synthetic fertiliser and herbicide requirements. They enhance biodiversity and support pollinator populations. Natural pest suppression, soil moisture retention, and temperature regulation contribute to sustainable production systems.

MB is nursery-raised and transplanted as seedlings (~320 seedlings/ha), never broadcast. A standard plantation legume mixture totals about 10-15 kg/ha across species. All other species require scarification before sowing. Use our Seed Calculator to calculate exact quantities for your field.

Choose based on shade tolerance and growth habit requirements.

An 8-year study documented $1,664/ha net benefit. Herbicide costs reduced by 50-90%. Nitrogen fertiliser savings of 30-70%. Additional gains from improved yields, reduced erosion, and lower labour costs. Widely adopted across SE Asian plantations.

Learn more: Evidence Hub | SoilBoost EA vs Compost

MB is extremely effective, suppressing weed density by 94.7-99.9% versus unweeded controls in oil palm inter-rows. All species suppress weeds through dense canopy formation, thick litter accumulation, and allelopathic compounds. Mechanisms include physical smothering, light competition, and rapid establishment that outcompetes weed growth.

Store on elevated pallets away from cement contact. Seeds maintain 80% germination for up to 5 years under ideal conditions. Most species require scarification. Keep moisture below 10% in cool, dry conditions with protection from pests.

Most tropical cover crops are perennial and do not require termination. Periodic slashing manages biomass accumulation. Mechanical cutting is used before cash crop planting. Circle weeding maintains clearance around young trees. Biomass can be incorporated as green manure.

CP produces high-quality livestock forage and hay. All species produce biomass suitable for mulching and composting. Harvest at maximum coverage for best results. CM is excellent as green manure in rice-based systems.

Validated by Rubber Research Institute India (RRII), Malaysian Palm Oil Board (MPOB), CIAT, and Queensland DPI. Long-term studies include an 8-year Nigeria trial and 16-year Queensland pasture trials. Decades of tropical research underpin these recommendations.

Import and export require permits from both origin and destination countries. Phytosanitary certificates are required for all shipments. Some species may be restricted due to invasive potential in certain regions. Always check local regulations before large-scale planting.