Collard greens are a primitive member of the Brassicaceae that are grown for their rosette of thick, dark green leaves, which are eaten primarily as cooked greens or pot herbs. Collards, along with most greens, are an excellent source of fiber
Stephen M. Olson and Joshua H. Freeman
Mark Farnham*, Glen Ruttencutter, Powell Smith, and Anthony Keinath
Collard (Brassica oleracea L., Acephala Group) is a uniquely American cole crop adapted to the southeastern United States, and several lines of evidence indicate its closest relative is heading cabbage (B. oleracea, Capitata Group). These two cole crops have been grown in close proximity in the Southeast from colonial times. Today, the number of commercially available collard cultivars is limited, and the most popular ones are susceptible to diseases like fusarium yellows, something that numerous cultivars of cabbage are highly resistant to. We postulated that hybrids between cabbage and collard would look more like collard because heading of cabbage is recessive to the nonheading nature of collard, and that such hybrids might be directly used as collard cultivars that express disease resistance from cabbage. Cytoplasmic male-sterile (cms) cabbage inbreds were crossed with different male-fertile collard inbreds using bees in cages to produce hybrid seed. Resulting cabbage-collard hybrids were compared to conventional collard and cabbage cultivars in three replicated field trials in South Carolina. In all trials, collard-cabbage hybrids exhibited similar size and stature as conventional collard, and throughout most of the growing season the hybrids remained nonheading. In addition, the collard-cabbage hybrids were much more uniform than open-pollinated collard cultivars. Among the cabbage-collard hybrids there was significant variation with some more collard-like than others. Results indicate that select collard-cabbage hybrids could out perform certain conventional collards and serve as potential new collard cultivars
Charles Zachry Ogles, Joseph M. Kemble, Amy N. Wright, and Elizabeth A. Guertal
, MO) and collards ( Brassica oleracea var. acephala cv. Blue Max) (Abbott and Cobb, Feasterville, PA). Materials and Methods Plant material and growth conditions. Field studies were conducted beginning on 6 July 2012 and continued until 26 Sept
Sandra E. Branham, Mark W. Farnham, Shane M. Robinson, and W. Patrick Wechter
(var. capitata ), cauliflower (var. botrytis ), kale (var. acephala ), Brussels sprout (var. gemmifera ), and collard in the United States alone (U.S. Department of Agriculture, National Agricultural Statistics Service, 2014). Collard is a leafy
Mark W. Farnham, Glen Ruttencutter, J. Powell Smith, and Anthony P. Keinath
Collard (Brassica oleracea L. Acephala Group) is a leafy green vegetable adapted to the southeastern United States. The number of commercially available collard cultivars is limited, and the most popular cultivars are susceptible to fusarium yellows, a disease that most cabbage (B. oleracea Capitata group) cultivars are resistant to. We hypothesized that hybrids of cabbage and collard would look more like collard, because heading of cabbage is at least partially recessive to the nonheading growth habit of collard. We also postulated that cabbage–collard hybrids might be used directly as collard cultivars. To test these postulates, cytoplasmic male sterile cabbage inbreds were crossed to different male fertile collard inbreds and hybrid seed was produced. Resulting cabbage–collard hybrids were compared to conventional collard cultivars in three replicated field trials in South Carolina. In all trials, cabbage–collard hybrids exhibited size and weight more similar to conventional collard than cabbage, and throughout most of the growing season the collards remained nonheading. In addition, the cabbage–collard hybrids were much more uniform than open-pollinated collard cultivars. Among cabbage–collard hybrids there was significant variation with some hybrids appearing more collard-like than others. The collard inbreds designated A and B may have the greatest potential for making promising cabbage–collard hybrids. Particular hybrids (i.e., A3 or B2), derived from these inbreds and tested in this study, can perform better than certain conventional collards and may serve as possible new cultivars of this vegetable crop.
Sharon J.B. Knewtson, Jason J. Griffin, and Edward E. Carey
planting as well as at 0, 1, and 5 weeks after planting. Fertilizer application was intended to follow optimal collard production recommendations while taking preplant soil analysis, texture, and previous management into account. Conventional fertilizer as
Francis M. Itulya, Vasey N. Mwaja, and John B. Masiunas
Field experiments were conducted in 1992 and 1993 to determine the effect of N fertility, cropping system, redroot pigweed (Amaranthus retroflexus L.) density, and harvesting frequency on collard (Brassica oleracea var. acephala D.C) and cowpea [Vigna unguiculata (L.) Walp.] growth. The N fertilization regimes were 0, 80, 160, and 240 kg·ha-1, applied as urea in a split application. Four weeks after crop planting, redroot pigweed was seeded at 0, 300, and 1200 seeds/m2. Between weeks 6 and 12, collard leaves were harvested at 1- to 3-week intervals. Year, N fertility, and cropping system interacted to determine collard leaf number and mass. For example, in 1992, with N at 160 kg·ha-1, collards intercropped had more total leaf mass than those monocropped. Pigweed density had no effect on collard yields, which were greatest from the 3-week harvest frequency. Cropping system and pigweed density interacted to determine cowpea vine length, shoot dry mass, and branching. The high density of pigweed caused a 56% reduction of cowpea dry mass in 1992.
E.A. Guertal and J.H. Edwards
Fall and spring collards (Brassica oleracea L. Acephala Group) were grown under one of three mulches (black plastic, ground newspaper, wood chips) and in a bare soil control. Mulch treatments were arranged in a factorial design with five rates of N fertilizer: 0, 67, 134, 201, or 268 kg N/ha. All fertilizer was preplant-incorporated into the bed before applying mulches and transplanting collards. Season did not affect collard yield, and there was no significant season × N rate interaction. Collard yields increased with increasing rates of N, with a maximum yield at 163 kg N/ha. Mulch type significantly affected collard yield, with fall collard yields highest under bare ground or wood chip mulches and spring yields highest under black plastic mulch. Collards produced under newspaper mulch produced the lowest yields in the fall and yields equal to bare soil and wood chips in the spring. Collards produced under newspaper mulch had less tissue N at harvest than those of any of the other treatments in both seasons. Collards produced on black plastic produced the lowest plant populations in both seasons. Wood chips and newspaper offer some appeal as low-input, small-scale mulches, but additional research to explore fertility management is necessary.
Robert J. Dufault, K. Dean Batal, Dennis Decoteau, J. Thomas Garrett, Darbie Granberry, Wayne McLaurin, Russell Nagata, Katharine B. Perry, and Douglas Sanders
The experiment screened two spring and two fall planting dates in six regions within North Carolina, South Carolina, and Georgia. The objective was to extend the production over the southeastern United States rather than at a single location. Spring harvests lasted from mid-April to early July. Summer-to-winter harvests lasted from mid-August to late January. Collards were not harvested in any of the locations from late January to mid-April or from early July to mid-August. More extensive planting dates may further increase the longevity of production.
Jon R. Johnson
The collard (Brassica oleracea, Acephala group) cultivar Vates was more susceptible than `Blue Max' to tipburn in sand-culture and field studies. Calcium concentrations in young leaves were similar for both cultivars. `Blue Max' appears to require a lower Ca concentration in young leaves than `Vates' for normal growth. In sand-culture studies, increasing the Ca level in nutrient solution to 3 mm or higher decreased tipburn in `Vates'. `Blue Max' did not develop tipburn regardless of Ca level. Increasing the Ca level in nutrient solution increased Ca concentration in young and old leaves for both cultivars. Soil application of CaSO4 or foliar application of Ca(NO3)2 or CaCl2 did not decrease occurrence of tipburn in Yates', presumably because these treatments did not increase Ca concentrations in young leaves.