Sowing Seeds in Rows (Line Sowing)
1.4 - Sowing seeds in rows (line sowing)
Kirsten Radcliffe, University of Guelph, Canada
Related video(s): Grow row by row (Source: Access Agriculture)
Suggested citation for this chapter.
Radcliffe, K. (2022) Sowing seeds in rows (line sowing). In Farmpedia, The Encyclopedia for Small Scale Farmers. Editor, M.N. Raizada, University of Guelph, Canada. farmpedia.org
Introduction
Traditionally, subsistence farmers have utilized a method known as broadcasting to sow seeds. Generally, broadcasting involves manually dispersing seeds throughout the field by throwing handfuls over the soil. In order for farmers to obtain a substantial yield with broadcasting, seeds must be sown at a relatively high density. Since the seeds are dispersed on the soil surface, some can be lost to birds or field run-off during rainstorms (Johansen et al., 2012). Alternatively, line sowing involves sowing seeds in uniform rows, either manually or with machinery (Food and Agriculture Organization, 2007). This sowing method allows for higher yields due to reduced plant competition for sunlight, water, and nutrients. Additionally, sowing seeds in rows allows for enhanced weed and pest management, since farmers can more easily move through the field to remove weeds and monitor crops for pests or disease (Barberi, 2002).
Benefits of Line Seeding
Sunlight, water, and nutrients are all essential components of plant development and growth. Plants absorb sunlight using the photo-pigments in their leaves, which is then converted into energy for growth (Maddonni and Martinez-Bercovich, 2014). Depending on the plant species, the efficiency of this conversion process differs slightly (Tesfaye et al., 2006). When plants become too crowded, competition for access to sunlight, nutrients, and water ensues.
Unfortunately, many farmers sow their crop seeds at a higher density than what is recommended by their local extension services, resulting in increased plant stress and a subsequent reduction in crop yields (Wiyo et al., 1999). Access to sunlight plays a major role in determining crop yield, as it is essential to plant growth. A study conducted by Maddonni and Martinez-Bercovich found that maize grain yield is primarily determined by kernel number per unit land, which is positively correlated with the amount of photosynthetically active radiation intercepted by the leaves (2014). Plants that emerge earlier have a competitive advantage in this situation, surpassing others in growth and eventually blocking surrounding plants' access to sunlight (Maddonni and Martinez-Bercovich, 2014). The larger the leaf size and the shorter the period required for leaf development, the greater the radiation interception. Singels and Smit conducted research on sugarcane and row spacing, finding that leaf development is affected by row spacing (2009). Higher rates of leaf development occurred in wider rows, indicating that plants require adequate space to access the sunlight and nutrients required for growth (Singels and Smit, 2009). Similarly, plants that are able to develop their root systems earlier will have greater success obtaining the scarce water and nutrients vital for growth (Barberi, 2002). The practice of sowing seeds in lines allows for optimum sunlight exposure and soil water utilization. Maddonni and Martinez-Bercovich found that grain yield reductions were most prevalent in fields where crops were planted at higher densities (2014). In addition, broadcasting tends to require higher seed input to compensate for losses, making line sowing a more beneficial choice when seed prices are high.
Sowing in rows enables farmers to monitor their crops for signs of pests or pathogens and gives them greater access to weeds. This is extremely important, as an unnoticed or untreated pest or pathogen could wipe out yields, leaving the farmer with no income or food for that season. Common bean (Phaseolus vulgaris L.), cowpea (Vigna unguiculata L.), chickpea (Cicer arietinum L.), and pigeon pea (Cajanus cajan L.) are major grain legumes grown in semi-arid regions (Tesfaye et al., 2006). These legumes are a primary source of dietary protein and income for subsistence farmers. Dry matter production and subsequent yield have been found to be highly associated with the fraction of photosynthetically active radiation (PAR) intercepted by the plant (Tesfaye et al., 2006). Studies conducted by Barberi using pigeon pea (Cajanus cajan L.) found that an inter-row distance of 40-50 centimetres allowed for optimal grain yields per unit and hoeing between rows (2001).
How to Practice
A simple method that can be employed to sow seeds in rows involves the use of string and wood stakes. Row spacing will vary depending on the region and species being planted. Measuring the dimensions of the field is recommended to ensure uniform spacing between rows (Food and Agriculture Organization, 2007). To ensure the rows are straight, tie the string to two wood stakes and place the stakes at either end of the field, making sure the string is tight. The string marks where the rows will be planted, acting as a visual guide for the sowing process. Seeds can either be dribbled into the furrows and covered over, or placed into a hole created using a hoe (Food and Agriculture Organization, 2007). The method involving a hoe to dig holes is typically used for larger crops, which require greater spacing (Food and Agriculture Organization, 2007). Mechanized tools are also available to farmers at a relatively low cost. Jab planters enable farmers to plant seeds into untilled soil, eliminating the labour of digging holes and bending down to plant seeds (Johansen et al., 2012). However, using this tool can bring challenges, such as the tip becoming clogged with soil, reducing its intended efficiency (Johansen et al., 2012). For line sowing to be most beneficial, it must be paired with a corresponding weed suppression strategy, such as a cover crop or herbicide treatment.
Picture Based Lesson to Train Farmers
South Asian version (pictures only, text for you to insert) — lesson 2.4
East/South Asian version (pictures only, text for you to insert) — lesson 2.4
Sub-Saharan Africa/Caribbean version (pictures only, text for you to insert) — lesson 2.4
Latin-America version (pictures only, text for you to insert) — lesson 2.4
North Africa and Middle East version (pictures only, text for you to insert) — lesson 2.4
Source: MN Raizada and LJ Smith (2016) A Picture Book of Best Practices for Subsistence Farmers. eBook, University of Guelph Sustainable Agriculture Kit (SAK) Project, June 2016, Guelph, Canada.
Challenges
Although planting seeds in rows is beneficial for yield levels, it is also considerably time-consuming. If farmers use manual line sowing methods, they will have to prepare the field for sowing with a hoe before they can distribute the seeds. Compared to broadcasting seeds, line sowing requires significantly more time and labour, which may deter farmers from adopting it, especially for lower-value crops. However, a farmer may be more inclined to adopt line-sowing practices for higher-value cash crops. For instance, farmers will almost always adopt line-sowing practices for many fruits and vegetables, which are high in labour, value, and input, and susceptible to pests and disease, whereas low-value cereals and legumes are more likely to be broadcast, since the perceived benefit of adopting line sowing is not as high. Broadcasting seeds at higher densities can also be beneficial for suppressing weed populations; if a farmer does not have the time or labour available to keep up with weeding, broadcasting may be a better option. The field being used by a farmer is not always located near their house, which limits access and time available for weeding, making broadcasting more attractive. Line sowing permits spaces between the rows of crops in which weeds can grow, whereas broadcasting leaves little space for weeds to develop. Furthermore, broadcasting can be successful in muddy soils, whereas line sowing, which may require machinery or a jab planter, tends to be problematic. Depending on the land, line sowing may require both a jab planter and a plough to loosen the soil first, whereas broadcasting may need no field preparation. When deciding between line sowing and broadcasting, it is very important to consider the crops being grown; some crops can be quite successful in mixed broadcasting, while others, such as corn, struggle due to shading.
References
1. Barberi, P. (2002). Weed management in organic agriculture: Are we addressing the right issues? Weed Research, 42, 177-193. Link
2. Food and Agriculture Organization. (2007). Labour saving technologies and practices: Row planting, hand seeders and planters.
3. Johansen, C., Haque, M.E., Bell, R.W., Thierfelder, C., & Esdaile, R.J. (2012). Conservation agriculture for smallholder rainfed farming: Opportunities and constraints of new mechanized seeding systems. Field Crops Research. DOI
4. Maddonni, G.A., & Martinez-Bercovich, J. (2014). Row spacing, landscape position, and maize grain yield. International Journal of Agronomy. Link
5. Singels, A., & Smit, M.A. (2009). Sugarcane response to row spacing-induced competition for light. Field Crops Research, 113, 149-155. DOI
6. Tesfaye, K., Walker, S., & Tsubo, M. (2006). Radiation interception and radiation use efficiency of three grain legumes under water deficit conditions in a semi-arid environment. European Journal of Agronomy, 25, 60-70. DOI
7. Wiyo, K.A., Kasomekera, Z.M., & Feyen, J. (1999). Variability in ridge and furrow size and shape and maize population density on small subsistence farms in Malawi. Soil & Tillage Research, 51, 113-119. Link