Cover crops for tropical plantations: the complete guide

Tropical legume cover crops between rows in an oil palm plantation

Cover crops are plants grown to cover and protect the soil rather than for harvest. In tropical oil palm and rubber plantations, leguminous cover crops (LCCs) are sown between young trees to fix nitrogen, reduce erosion and weeds, and build soil organic matter. The main species used in Southeast Asia are Mucuna bracteata, Pueraria javanica, Calopogonium mucunoides, Centrosema pubescens, and Calopogonium caeruleum.

Why plantations grow cover crops

  • Nitrogen: legume cover crops fix atmospheric nitrogen and contribute it to the system during the immature phase
  • Erosion control: a living cover protects soil from rainfall impact and runoff on slopes
  • Weed suppression: dense ground cover shades out weeds and reduces the weeding needed
  • Soil organic matter: heavy biomass and leaf litter feed soil organic matter and biology
  • Moisture: ground cover helps retain soil moisture during dry spells

What is a leguminous cover crop?

A leguminous cover crop is a legume grown for ground cover rather than grain. Through a partnership with Rhizobium bacteria in their roots, legumes fix nitrogen from the air and make part of it available to the system. In plantations they are established between rows of young palm or rubber, where they cover bare soil quickly and add organic matter as they grow and decompose.

The five main species

Each species suits different conditions. Use the overview below, then see the detailed guides and product pages.

For a side-by-side view, see the five-species comparison.

Small seeds held in an open palm
Seeding rates depend on seed size, germination rate and how fast the block needs covering.

Seeding rates

Species Recommended seeding rate (sown alone) In a mixture
Pueraria javanica (PJ) 10 kg/ha sown alone (Chemiseed recommendation, 2026 catalogue) Set on the quotation
Calopogonium mucunoides (CM) 10 kg/ha sown alone (Chemiseed recommendation, 2026 catalogue) Set on the quotation
Centrosema pubescens (CP) 10 kg/ha sown alone (Chemiseed recommendation, 2026 catalogue) Set on the quotation
Calopogonium caeruleum (CC) 5 kg/ha sown alone (Chemiseed recommendation, 2026 catalogue) Set on the quotation
Mucuna bracteata (MB) 1 kg/ha sown alone, drilled or planted in holes (Chemiseed recommendation, 2026 catalogue); in a mixture, set on the quotation. MB is not broadcast; it can also be raised in a nursery and transplanted: in MPOB's trial on deep peat, 320 seedlings/ha, two per palm point, were raised from about 500 seeds (75 g) (MPOB TT No. 501), and Samedani et al. (2015) planted 680 seedlings/ha on mineral soil.

Mixtures

These rates are for one species sown alone. For a mixture, the quantity of each species is set on the quotation for your site. For the record, MPOB's trial on deep peat, MPOB TT No. 501 (Information Series 588, June 2012; Hasnol Othman, Farawahida Mohamad Darus & Zulkifli Hashim), 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. That is what that peat trial used, not a recommended rate or a starting point; MPOB does not state whether the 8 kg/ha is per gross hectare or per interrow hectare actually sown.

Two distinctions are worth stating before you order: a mixture's total is not the rate of each species in it, and a gross hectare is not the interrow hectare you actually sow. The quantity for your site is confirmed on the quotation. There is also no Philippine institutional rate: PNS/BAFS 238:2018 (PCA) recommends legume cover cropping but gives no rate, so any Philippine figure is an extrapolation from Malaysian practice. Plan exact quantities with the cover crop calculator.

How to choose a cover crop

Match the species to the crop and growth stage. For oil palm, see best cover crop for oil palm by growth stage; for rubber, see best cover crop for rubber by canopy stage. If the priority is slope protection, see cover crops for erosion control; for inter-row weed pressure, see cover crops for weed suppression.

Frequently asked questions

What is a cover crop?
A plant grown to cover and protect the soil rather than for harvest. In plantations, leguminous cover crops fix nitrogen, reduce erosion and weeds, and build soil organic matter.

Which cover crop is best for oil palm?
It depends on estate age and conditions. PJ and CM, drilled or planted in holes, establish fast on open and immature ground; MB holds under a maturing canopy and grows vigorously through that phase; CP and CC are the shade-persistent successors for older stands. Many estates use a mixture.

How much cover crop seed per hectare?
The recommended seeding rate, sown alone, is 10 kg/ha for PJ, CM and CP, 5 kg/ha for CC and 1 kg/ha for MB, drilled or planted in holes (Chemiseed recommendation, 2026 catalogue). These rates are for one species sown alone. For a mixture, the quantity of each species is set on the quotation for your site. MB is not broadcast; it can also be raised in a nursery and transplanted, and in MPOB's trial on deep peat, 320 seedlings/ha, two per palm point, were raised from about 500 seeds (75 g) (MPOB TT No. 501).

How much nitrogen do cover crops fix?
Less precisely than most published tables imply, and we would rather set out what is actually measured than give you one number per species. PJ: up to 250 kg N/ha/yr accumulated in aboveground biomass at 85 to 93% Ndfa, from a single rubber-intercrop trial in northeast Thailand (Clermont-Dauphin et al. 2016, Agriculture, Ecosystems & Environment 217:79-88). That is a measured upper reference point from one site, not a design value, and the same trial found the cover reduced the drought resilience of the young rubber on water-limited ground. MB: 67 to 84% of its nitrogen drawn from the atmosphere by 15N isotope dilution (Cheah, Zaharah & Aminuddin 2010, Oil Palm Bulletin 60): a proportion, not a quantity, and we do not publish an absolute kg figure for MB. CP and CM: no verified species-specific nitrogen figure is published. CC: no species-specific annual rate; one Papua New Guinea oil palm study estimated 28 to 75% Ndfa (Pipai et al. 2023).

Important: Cover crops are an agronomic ground-cover and soil-health practice. They are not a fungicide, pesticide, or treatment for Fusarium TR4, Phytophthora, or any crop disease. They may support soil structure 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.

Related reading

Source cover crop seed for your plantation

Chemiseed supplies all five tropical cover crop species with seed tested for germination and purity to ISTA and AOSA methods, and agronomic support. Browse the cover crop seeds collection, request a quotation, or plan quantities with the cover crop calculator.

Sources: Clermont-Dauphin et al. (2016), Agriculture, Ecosystems & Environment 217:79-88; Cheah, Zaharah & Aminuddin (2010), MPOB Oil Palm Bulletin 60; MPOB TT No. 501 / Information Series 588 (June 2012); Samedani et al. (2015), Int. J. Agric. Biol. 17(2): 251-260; Pipai et al. (2023), Plant and Soil 491:665-680; seeding rates: Chemiseed recommendation (2026 catalogue). Figures are presented with method and context; results depend on site, soil, rainfall, and management. Last reviewed October 2026.