Released from the breeding program of W.R. Okie, USDA-ARS, Byron, GA in 1989. Rubysweet is a Japanese-type plum that resulted from a cross of Mariposa and Methley by V.E. Prince. It is a large, high-quality plum that ripens in mid-late June and is well adapted to the humid climate of the southeastern United States. It blooms with Bruce and Methley, about 2 days before Santa Rosa. Flowers are white, 2 cm in diameter, and in clusters of 2-3. Pollen shed is moderate and apparently self-incompatible, so Rubysweet should be planted adjacent to other plums blooming at the same time to facilitate insect pollination. In most years, thinning has been required to reduce fruit set. Fruit of Rubysweet ripen between Santa Rosa and Ozark Premier, about the 3rd week of June at Byron, GA. Skin color is reddish-gold bronze, which is masked by a heavy bloom. The blood red flesh is firm and of very good quality. With proper thinning, 2 inch (5 cm) fruit diameter is common. Fruit shape is round. The pit is freestone and of medium size. Trees of Rubysweet are moderately vigorous on peach rootstock. Tree health is better than Santa Rosa or Ozark Premier but less than Robusto or Byrongold. Rubysweet is moderately resistant to leaf spot or twig cankers caused by Xanthomonas campestris pv pruni and to trunk cankers caused by Pseudomonas syringae pv syringae. It is tolerant of the xylem-limited bacteria Xylella fastidiosa which causes plum leaf scald.
Key
Evaluations are based on a 1-8 scale (6=OK,7=Commercially acceptable, 8=Excellent)
Size is in inches
Shape: round is assumed, T=tip, P=point, S=suture, OB=oblate, OV=ovate
Pubescence: 10=nectarine
Blush: presented as percentage of ground color cover with red or similar
Freeness: 3=early cling, 8=completely free
Status: 0=discard, 1=keep
Notes: SOS=soft on suture, SOT=soft on tip, RIF=red in flesh, GAS=green around stem
RAP=red around pit, GGC=green ground color, sz=size, wh=white, yt=young tree, CCT=concave tip
Bloom date is when approx. 90% of blooms are open (full bloom)
The description of each variety of peach or nectarine fruit under each group is in different formats as this information is collected from varied sources and hence is not consistent