Starting a cover crop program on a Philippine plantation can be a worthwhile agronomic investment, but many estate managers delay because the process feels complex or unfamiliar. This guide breaks the implementation into concrete, sequential steps that any estate, from smallholder coconut farms in Quezon to large oil palm blocks in Mindanao, can follow from planning through first-year management.
Step 1: Define Your Primary Objective
Cover crops deliver multiple benefits simultaneously, but your primary objective determines species selection, planting priority, and how you measure success. Identify which of these is your top priority:
- Weed suppression: Reducing herbicide and manual weeding costs
- Erosion control: Protecting topsoil on slopes during typhoon season (critical in Visayas and Eastern Mindanao)
- Nitrogen fixation: Legume cover contributes nitrogen; confirm what it supplies with soil and leaf analysis before adjusting fertiliser
- Soil rehabilitation: Restoring organic matter, structure, and water-holding capacity on degraded or compacted soils
- RSPO/sustainability compliance: Meeting certification requirements for ground cover between plantation rows
Your primary objective narrows species selection immediately. Weed suppression favours aggressive species (MB, CM). Erosion control favours deep-rooted species (MB on slopes, PJ on moderate terrain). Nitrogen fixation is delivered by all legume species, and there are no like-for-like figures to rank them by nitrogen fixed, so choose among them on your other objectives. Soil rehabilitation benefits most from high-biomass species (MB, CM).
Step 2: Map Your Blocks by Condition
Not all blocks on your estate have the same conditions. Walk your blocks and categorise each one by:
| Factor | Category A | Category B | Category C |
|---|---|---|---|
| Shade level | Low | Moderate | Heavy |
| Slope | Flat | Moderate | Steep |
| Weed pressure | Low | Moderate | Heavy (Imperata/Mikania) |
| Drainage | Well-drained | Seasonal wet | Poorly drained |
| Crop age | Young (immature) | Mid-age | Mature |
Each block's combination of factors points to the optimal species. You will likely need more than one species (or mix) across your estate rather than a single species everywhere.
Step 3: Select Species for Each Block Type
Based on your block mapping, assign species (see our 5-species cover crop comparison for detailed traits):
- Category A blocks (low shade, flat, young palms): Pueraria javanica (PJ) alone, or PJ + Calopogonium mucunoides (CM) mix for faster initial cover; in mixtures CM is the first to establish and also the first to be shaded out (PROSEA 11)
- Category B blocks (moderate shade, moderate slopes, mid-age palms): Mucuna bracteata (MB) for weed suppression and erosion control, or PJ; PJ also twines and climbs tree stems unless the circles are kept clean (PROSEA 11), so plan for circle and trunk clearing with either
- Category C blocks (heavy shade, mature palms): Centrosema pubescens (CP) or Calopogonium caeruleum (CC), two species that persist under heavy canopy
- Heavy Imperata blocks (any shade level): MB after thorough chemical cleanup of existing cogon grass
- Poorly drained blocks: open drains first; once established, PJ tolerates wet and even waterlogged sites (PROSEA 11), but sow where water does not pond, so seed and seedlings are not washed out or drowned
Step 4: Calculate Seed Requirements and Budget
For each species and block area, calculate seed needs:
| Species | Recommended Seeding Rate (sown alone) | Method |
|---|---|---|
| Pueraria javanica (PJ) | 10 kg/ha sown alone | Drilled or in holes |
| Mucuna bracteata (MB) | 1 kg/ha sown alone, drilled or planted in holes; nursery seedlings are another option (MPOB's deep-peat trial: 320 seedlings/ha, two per palm point, from about 500 seeds, 75 g, MPOB TT No. 501; Samedani et al., 2015: 680 seedlings/ha on mineral soil) | Drilled or in holes, or nursery seedlings; not broadcast |
| Calopogonium mucunoides (CM) | 10 kg/ha sown alone | Drilled or in holes |
| Centrosema pubescens (CP) | 10 kg/ha sown alone | Drilled or in holes |
| Calopogonium caeruleum (CC) | 5 kg/ha sown alone | Drilled or in holes |
Source of the recommended rates: our recommendation, each for one species sown alone. For example, 25 ha sown alone needs 250 kg of PJ, CM or CP, 125 kg of CC, or 25 kg of MB. For a mixture, the quantity of each species is set on the quotation for your site. For the record, MPOB's peat trial (MPOB TT No. 501, Table 1 treatment C2) used PJ 4 + CP 3 + CC 1 = 8 kg/ha, which MPOB calls conventional LCC, with 5 g of Rhizobium (RRI strain) inoculant per kg of seed.
Recommended planting method: drill or in holes. Broadcasting does not guarantee good germination, especially where the soil dries out easily. Seed quantities for your blocks are confirmed on the quotation. Budget should also include site preparation labour, planting labour (which depends on the method), and first-year maintenance for palm circle clearing.
Step 5: Time Your Planting Window
In the Philippines, optimal planting timing varies by region:
- Areas with a distinct dry season (Type I climate, for example Western Visayas and western Luzon): Plant at the onset of the wet season, when consistent moisture supports germination but rainfall is not yet at typhoon intensity
- Eastern Visayas and Eastern Mindanao (Type II climate, no dry season and a pronounced period of maximum rain): Plant outside the period of maximum rainfall, when the soil is moist but not waterlogged
- Much of Mindanao (Type III/IV climate): More evenly distributed rainfall allows planting over a longer part of the year; avoid the months when your area floods
The critical rule: ensure consistent soil moisture for the weeks after seeding, without waterlogging events that kill young seedlings. Check the PAGASA climate type and local rainfall records for your estate.
Step 6: Prepare Your Sites
Complete site preparation ahead of your target seeding date:
- Weed clearing: Slash and/or spray existing vegetation. For Imperata, apply glyphosate according to the label and wait for complete dieback before proceeding.
- Debris removal: Clear fallen fronds, coconut husks, and thick mulch that prevent seed-soil contact.
- Soil pH check: Where the soil is strongly acid, apply dolomite lime at the rate your soil analysis recommends. Nitrogen-fixing bacteria (Rhizobium) that power cover crop benefits are impaired in very acid soils.
- Drainage assessment: Open blocked drains and mark areas prone to standing water, so you can sow them once they drain.
- Mark palm circles: Delineate the circles around each palm/tree trunk that will be kept cover-crop-free.
Step 7: Plant and Establish
For seed drilled or planted in holes (PJ, CM, CP, CC), our recommended planting method:
- Mark out drill lines or planting holes in systematic parallel rows across the prepared surface
- Mix seed with dry sand for even distribution along the drills
- Sow the seed into the drills or holes
- Cover lightly and firm the soil to improve seed-soil contact (keep seed close to the surface)
- If rain does not follow soon after seeding, irrigate if possible, or wait for forecast rain before seeding
For MB: our recommended seeding rate is 1 kg/ha sown alone, drilled or planted in holes as above. MB is not broadcast. Raising MB in a nursery and transplanting the seedlings is another option:
- Start the nursery ahead of the target field transplanting date
- Scarify seeds (nick the seed coat or soak them) before nursery sowing
- Transplant seedlings at the density set for your block (see Step 4) once they are sturdy enough to handle
- Water transplants if no rain follows transplanting
Step 8: The Critical Establishment Period
The first months after sowing determine long-term success. During this period:
- First weeks: Monitor germination. If emergence is patchy, identify the cause (too dry, too deep, seed quality) and reseed gaps immediately.
- As seedlings establish: Spot-weed around seedlings if aggressive weeds are overtopping the cover crop. The need for spot-weeding usually falls once the canopy closes.
- As runners extend: Monitor runner extension and canopy coverage. Published establishment times give a guide: PJ reached 60 to 70% cover after about 4 months and 90 to 100% after 8 months in Malaysia (PROSEA 11); CM covers the soil 3 to 6 months after sowing and forms a dense sward at 4 to 5 months (PROSEA 11); MB reached about 100% cover at 6 months on mineral soil (Samedani et al., 2015) but only 31% at 6 months on deep peat (MPOB TT No. 501).
- Canopy closing phase: Reduce weed management inputs as cover crop takes over suppression role.
If typhoon damage occurs during establishment (relevant for Philippine planting windows), assess coverage after the event. If large parts of the stand are destroyed, reseed the damaged areas promptly rather than waiting for natural recovery.
Step 9: Ongoing Management and Fertiliser Adjustment
Once your cover crop has closed over the interrows:
- Palm circle clearing: Schedule it regularly. This is a routine maintenance cost on every block; blocks with climbing covers also need trunk clearing (below).
- Trunk clearing (climbing covers such as MB and PJ): Remove climbing vines from palm/tree trunks as often as needed to keep them off the trunk and fronds.
- Nitrogen fertiliser adjustment: Legume cover contributes nitrogen; adjust your fertiliser programme only after soil and leaf analysis shows what the cover supplies on your block. Cutting nitrogen ahead of that evidence can affect yield.
- Annual assessment: Walk blocks at least once per year to identify thinning areas (usually due to increasing shade) and interplant with shade-tolerant species where needed.
Step 10: Measure and Document Results
Track these metrics to see what the program does on your estate:
- Herbicide expenditure per hectare (before vs. after cover crop establishment)
- Manual weeding labour days per hectare per year
- Nitrogen fertiliser application rate (before vs. after)
- Visual erosion indicators (rill formation, exposed roots, soil colour in runoff)
- Soil organic matter percentage (annual soil test)
Results vary by site and season, so compare these figures year on year to see what the program returns on your estate.
Getting Started
The most common mistake is over-planning and under-executing. Start with your worst block: the one with the highest weed costs, steepest erosion, or most degraded soil. Establish cover crop on that block first, document the process and results, then scale the approach across your estate based on proven outcomes.
Kudzu Seeds Trading supplies five legume cover crop species for Philippine plantations, with agronomic guidance on species selection and establishment for your specific conditions. Request a consultation or contact us on WhatsApp to discuss your estate requirements.
Related Resources
- 5-Species Cover Crop Comparison
- Best Cover Crop for Oil Palm
- Best Cover Crop for Rubber
- Cogon Grass Control with Cover Crops
Sources
- Halim, R.A. (1997). Pueraria phaseoloides (Roxb.) Benth. In: Faridah Hanum, I. & van der Maesen, L.J.G. (eds), Plant Resources of South-East Asia No. 11: Auxiliary plants. Backhuys Publishers, Leiden. Reproduced on Pl@ntUse: Pueraria phaseoloides (PROSEA)
- Chen Chin Peng & Aminah, A. (1997). Calopogonium mucunoides Desv. In: Faridah Hanum, I. & van der Maesen, L.J.G. (eds), Plant Resources of South-East Asia No. 11: Auxiliary plants. Backhuys Publishers, Leiden. Reproduced on Pl@ntUse: Calopogonium mucunoides (PROSEA)
- Tropical Forages: an interactive selection tool (2020 edition, CIAT and ILRI): tropicalforages.info
- Hasnol Othman, Farawahida Mohamad Darus & Zulkifli Hashim (2012). Best management practices for oil palm cultivation on peat: Mucuna bracteata as ground cover crop. MPOB Information Series 588 / MPOB TT No. 501. Malaysian Palm Oil Board. MPOB PDF
- Samedani, B., Juraimi, A.S., Rafii, M.Y., Sheikh Awadz, S., Anwar, M., & Anuar, A.R. (2015). Effect of cover crops on weed suppression in oil palm plantation. International Journal of Agriculture and Biology, 17(2), 251-260. CABI PDF