Establishment of rhizoma peanut: Interaction of cultivar, planting date, and location on emergence and rate of cover

Rhizoma perennial peanut (RPP), Arachis glabrata Benth., has high nutritive value, drought tolerance, and persistence; however, inconsistent establishment success and slow rate of coverage has limited the use of RPP in production systems. The objectives of this study were to determine the effects of planting date (February, April, June, August, and December), location (Brooksville, Gainesville, and Quincy, FL), and cultivar (Florigraze and Arbrook) on emergence (sprouts per square meter at 2 to 12 wk post planting) and rate of RPP cover (percent ground cover at 26, 52, 78, and 104 wk post planting). We also determined the relationship of sprout counts during the emergence period with rate of cover. Number of sprouts per square meter at 12 wk post planting ranged from 0 to >200 and, in most cases, the sprout counts obtained for April, June, August, and December planting dates were lower or equal to those from the February planting date, regardless of location or cultivar, Generally, Arbrook had higher numbers of sprouts per square meter at 12 wk post planting than Florigraze, but this did not translate into higher ground cover ratings at 26 wk. Number of sprouts per square meter was positively correlated with percent ground cover. The highest correlation coefficient (0.69) occurred for the relationship of sprouts per square meter at 12 wk post planting and ground cover at 26 wk post planting; correlations of responses declined from that point as stands aged. Rate of cover was also variable, taking between 26 and >104 wk post planting to reach >60% RPP ground cover. On average, February plantings achieved >60% RPP ground cover 26 wk earlier than any of the other planting dates. This study indicates that establishment times for RPP can be more variable than has been thought. The first criterion for deciding when to plant is the need for reliable soil moisture (from rainfall or irrigation) for 60 to 90 d post planting. Secondly, if there is more than one time of the year that meets this moisture requirement, then the planting date with the longest frost-free period after planting should be chosen.