Date of Award
5-2026
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Plant and Environmental Science
Committee Chair/Advisor
Dil Thavarajah
Committee Member
Emerson Shipe
Committee Member
Thava Thavarajah
Abstract
Field peas (Pisum sativum L.) are not widely cultivated in South Carolina, resulting in limited agronomic data to support farmers interested in this crop. However, field peas hold significant promise as a cool season crop for both organic and conventional growers in the region. Most commercially available field pea cultivars are evaluated and bred for the Pacific Northwest, where environmental conditions differ substantially from those in the southeastern United States. Consequently, there is a lack of region-specific recommendations for successful cultivation in South Carolina. To address this gap, a two-year planting date study was conducted during the 2020–2021 and 2021–2022 growing seasons to identify the optimal planting window for field peas in South Carolina. Five high-performing commercial cultivars were selected based on prior multi-year trial data. Four cultivars were chosen to represent a range of maturity classes and growth habits.. The study utilized a randomized complete block design (RCBD) with four planting date treatments, each spaced approximately 14 days apart, except for the final planting. Planting dates ranged from mid-October to late January. Each planting date block included three replicates per variety and was bordered to minimize edge effects. Entries were agronomically evaluated every 21 to 28 days using the Pheno App 'Field Book' weekly to assess vigor, growth, and agronomic performance.
Across both years of the study, results consistently demonstrated that the latest planting date (Planting Date 4, late January) produced significantly higher yields and superior agronomic performance compared to earlier planting dates. Early planting dates were adversely affected by low temperatures, elevated precipitation, and extended cropping cycles. Freezing conditions during key developmental stages, particularly the vegetative and flowering phases, resulted in increased susceptibility to frost damage. This exposure led to irreversible damage to plant tissues, resulting in either complete crop failure or severe reductions in agronomic performance. These differences were statistically significant, underscoring the importance of planting time in optimizing field pea production under South Carolina conditions. The early-maturing cultivars outperformed late-maturing ones, suggesting that shorter growth cycles may offer resilience against environmental stressors. The study further highlighted the critical role of climate and growth cycle duration in field pea development. These findings emphasize the need for region-specific planting recommendations that account for climatic variability and phenological sensitivity to ensure successful field pea cultivation in the southeastern United States.
Recommended Citation
Lawrence, Tristan, "Field Pea (Pisum sativum L.) Response to Planting Date in South Carolina Organic Cropping Systems" (2026). All Theses. 4712.
https://open.clemson.edu/all_theses/4712
Author ORCID Identifier
0000-0003-0899-0136