Calculate effective plant populations and Land Equivalency Ratio (LER) for intercropped systems. Optimize companion crop spacing for maximum productivity.
Intercropping — growing two or more crops simultaneously on the same land — can increase total productivity per acre when crop competition is managed through proper spacing. The Land Equivalency Ratio (LER) measures whether the intercrop outperforms growing each crop separately by comparing combined relative yields.
This calculator estimates the effective plant populations for two crops in an intercropped system and computes the LER based on expected yield fractions. A LER greater than 1.0 means the intercrop produces more total output per acre than growing each crop in monoculture on separate land.
Use this tool to design strip-intercropping, relay-intercropping, or mixed-row planting arrangements. Whether you are a beginner or experienced professional, this free online tool provides instant, reliable results without manual computation. By automating the calculation, you save time and reduce the risk of costly errors in your planning and decision-making process. This tool handles all the complex arithmetic so you can focus on interpreting results and making informed decisions based on accurate data.
Intercropping can improve land use efficiency by 20-40% when well-designed, but poor spacing choices lead to excessive competition and yield losses. This calculator helps you find the sweet spot where both crops contribute meaningfully to total output. Having a precise figure at your fingertips empowers better planning and more confident decisions.
LER = (Yield_A_intercrop / Yield_A_sole) + (Yield_B_intercrop / Yield_B_sole) Effective Population = Pop_A + Pop_B × Competition factor LER > 1.0 indicates intercrop advantage over monoculture.
Result: LER = 1.15
If corn yields 60% and beans yield 55% of their respective monoculture yields when intercropped: LER = 0.60 + 0.55 = 1.15. The intercrop uses land 15% more efficiently than separate monocultures.
Row intercropping alternates rows of different crops. Strip intercropping uses wider strips of each crop, typically matching equipment widths. Relay intercropping plants the second crop into a standing first crop before harvest. Mixed intercropping sows species together without distinct rows.
High LER results from complementary resource use. A classic example is a tall C4 cereal (efficient in full sun) paired with a shade-tolerant legume (fixes its own nitrogen). The cereal captures upper canopy light while the legume uses understory light that would otherwise be wasted.
Intercropping often requires more management, specialized harvest procedures, and careful market planning for two products. However, the total revenue per acre can exceed monoculture when LER is above 1.0 and both crops have viable markets.
LER compares the land area needed by monocultures to produce the same output as the intercrop. An LER of 1.15 means you would need 15% more land to match the intercrop's output using separate monocultures.
Common combinations include corn + beans (Three Sisters tradition), cereal + legume (wheat + peas), sorghum + cowpea, cassava + beans, and strip-cropped arrangements of corn and soybeans. These pairings work well because the species differ in canopy height, rooting depth, and nutrient requirements, which reduces direct competition. Local university extension trials can help identify the best combinations for your climate and soil conditions.
Use spatial separation (strip cropping), temporal separation (relay planting), or choose species that occupy different niches (canopy layers, rooting depths, nutrient demands). Proper spacing and species selection are the primary management tools.
Strip intercropping is practical with standard equipment — each strip is wide enough for a planter pass and harvester pass. Mixed-row intercropping is harder to mechanize and is more common in smallholder and intensive horticulture systems.
Often yes. Greater crop diversity can confuse pest insects, reduce disease spread between host plants, and support beneficial insect populations. However, the effect varies by crop combination and local pest complex.
The competition factor estimates how much one crop's growth is suppressed by the presence of the other. A factor of 0.5 means the crop achieves about half its monoculture productivity. Actual values depend on species, spacing, and environment.