Rhizoma peanut (Arachis glabrata Benth.) is a leguminous, herbaceous, dinitrogen-fixing, warm-season perennial native to South America. It has been used almost exclusively as a forage crop in the United States since the 1930s. While hard frosts kill aboveground foliage, rhizoma peanut is grown in U.S. Department of Agriculture hardiness zones 8b and greater of peninsular Florida and the U.S. Southern Coastal Plain where it is best adapted to coarse, sandy soils (Ocumpaugh, 1990; Prine et al., 1990; Terrill et al., 1996). However, its utility as an ornamental groundcover has not been realized. Extensive soil colonization by its rhizomes, which can account for up to 85% of the plant’s biomass (Williams, 1994), make it drought-tolerant and persistent once established (Ortega-S. et al., 1992; Prine et al., 1990). Additionally, it is pest and disease resistant (Baltensperger et al., 1986; Quesenberry et al., 2010), fixes nitrogen to support its growth (Venuto et al., 1998), produces abundant flowers, and has high aesthetic value as an ornamental groundcover (Prine et al., 2010) (Fig. 1). Rhizoma peanut has the potential to be used in diverse situations, including roadside and right-of-way plantings, and as an ornamental or utility turf, including areas where mowing is difficult, such as sloped or uneven terrain.
Previous research on rhizoma peanut has focused almost entirely on the forage cultivar Florigraze. Cultivars Arbrook (Butler et al., 2006), UF Peace, and UF Tito were subsequently released as superior forages based on yield and drought tolerance (Quesenberry et al., 2010). In contrast, lower growing forms of rhizoma peanut have received little attention for their potential use as an ornamental groundcover. Compared with forage cultivars, ‘Ecoturf’, ‘Brooksville 67’, and ‘Brooksville 68’ maintain lower canopies and show promise as ornamental groundcovers or turf alternatives. During drought conditions, ‘Ecoturf’ outperformed St. Augustinegrass (Stenotaphrum secundatum Kuntze), as measured by leaf color and visual appearance (Prine et al., 2010).
Generally, rhizoma peanut does not achieve full cover for at least 2 years (Adjei and Prine, 1976; Williams et al., 1997), necessitating the need for selections that provide faster cover, a characteristic of great ornamental importance. Successful cultivation of rhizoma peanut in a shaded environment allows for greater planting options. In one of only a few studies addressing rhizoma peanut shade tolerance, ‘Florigraze’, grown under 54% photosynthetic photon flux density (PPFD), persisted comparably to that grown under full sun (Johnson et al., 1994). However, no selections have been evaluated for ornamental attributes in full sun vs. shaded environments.
Environmental conditions may play less of a role in establishment of rhizoma peanut than planting material genetics (Williams, 1993). Furthermore, selections overlooked in forage evaluations may have desirable ornamental characteristics. Water resource scarcity, as a result of population needs and the overuse of chemical fertilizers have dictated the need for more environment-friendly groundcovers. Rhizoma peanut has the potential to fill this need; however, ornamentally important characteristics have not been studied among cultivars (Prine et al., 2010). In addition, new ornamental cultivars will expand commercially available germplasm diversity.
The objectives of this study were to characterize the rate and duration of full canopy cover, as well as height attributes of previously released and new selections of rhizoma peanut, in full sun and under shade. Height attributes included maximum average canopy height and canopy uniformity, which were used for selecting low-growing selections with minimal canopy height variability. These characteristics were used to propose selections for ornamental use.
Aldrich, J.H., Knox, G.W., Blount, A.R. & Mackowiak, C.L. 2012 Landscape performance of mowed rhizoma perennial peanut. Proc. So. Nurs. Res. Conf. 57:197–200
Butler, T.J., Ocumpaugh, W.R., Sanderson, M.A., Reed, R.L. & Muir, J.P. 2006 Evaluation of rhizoma peanut genotypes for adaptation in Texas Agron. J. 98 1589 1593
FAWN 2015 Florida Automated Weather Network Report Generator. University of Florida, Gainesville, Florida. 23 Feb. 2015. <http://fawn.ifas.ufl.edu/data/reports/>
Johnson, S.E., Sollenberger, L.E. & Bennett, J.M. 1994 Yield and reserve status of rhizoma peanut growing under shade Crop Sci. 34 757 761
Ortega-S., J.A., Sollenberger, L.E., Quesenberry, K.H., Cornell, J.A. & Jones, C.S. Jr 1992 Productivity and persistence of rhizoma peanut pastures under different grazing managements Agron. J. 84 799 804
Prine, G.M., French, E.C., Blount, A.R., Williams, M.J. & Quesenberry, K.H. 2010 Registration of Arblick and Ecoturf rhizoma peanut germplasms for ornamental or forage use J. Plant Registr. 4 145 148
Quesenberry, K.H., Blount, A.R., Mislevy, P., French, E.C., Williams, M.J. & Prine, G.M. 2010 Registration of ‘UF Tito’ and ‘UF Peace’ rhizoma peanut cultivars with high dry matter yields, persistence, and disease tolerance J. Plant Registr. 4 17 21
Terrill, T.H., Gelaye, S., Mahotiere, S., Amoah, E.A., Miller, S., Gates, R.N. & Windham, W.R. 1996 Rhizoma peanut and alfalfa productivity and nutrient composition in central Georgia Agron. J. 88 485 488
Venuto, B.C., Redfearn, D.D. & Pitman, W.D. 1998 Rhizoma peanut responses to harvest frequency and nitrogen fertilization on Louisiana coastal plain soils Agron. J. 90 826 830
Williams, M.J. 1993 Planting date and preplant tillage effects on emergence and survival of rhizoma perennial peanut Crop Sci. 33 132 136
Williams, M.J., Kelly-Begazo, C.A., Stanley, R.L. Jr, Quesenberry, K.H. & Prine, G.M. 1997 Establishment of rhizoma peanut: Interaction of cultivar, planting date, and location on emergence and rate of cover Agron. J. 89 981 987
Your Weather Service 2015 US Climate Data. 23 Feb. 2015. <http://www.usclimatedata.com/>