Cultivar 359: Delta

Delta is a University of Saskatchewan Prunus introduction from 1960. It is recorded as a cross of Sapa x Oka, and the prairie cultivar index lists that parentage. University release tables list it as introduction C59-354, placing it in the mid century Saskatchewan breeding work on hardy prairie plum and cherry plum material. [S1] [S3]

At introduction, the fruit was described as spherical, bluish black, with dark red flesh and a sweetish flavor of good quality. [S3] A Saskatchewan characteristics table gives more detail: fruit about 3/4 inch in diameter, green splotched with purple, with thin, relatively tender skin, dark purple juicy flesh, and a sweet flavor that turns astringent just below the skin. That table rates dessert quality as only fair. [S2] Together, the sources describe a small dark fruited hybrid with red to dark purple flesh and better quality than many utility plums, but with some sharpness near the skin. [S2] [S3]

Delta is mainly of historical interest. It is one of the University of Saskatchewan Sapa x Oka selections that expanded prairie breeding material and helped define a group of cold climate Prunus hybrids adapted to Saskatchewan conditions. [S1] [S3] The surviving sources here do not give a fuller tree description, crop habit, storage life, or a direct hardiness rating for this cultivar, so those points remain open.

Summary source basis

• S1: An index of fruit cultivars tested or developed on the Canadian prairies.
• S2: hortfacts_1976_3.pdf
• S3: University of Saskatchewan fruit introductions 1959-1960

This summary currently draws chiefly from hortfacts_1976_3.pdf, with 2 additional supporting sources linked below.

Featured source descriptions

“Skin described as thin and relatively tender; flesh as dark purple and juicy.”
— ^[3]

“Tested primarily in Zones 4 and 5, where it showed moderate to severe winter injury.”
— ^[3]

“Flavor described as sweet, but astringent just below skin.”
— ^[3]

“Dessert quality listed as fair.”
— ^[3]

Direct parent cultivars

• No direct linked parent cultivars promoted yet.

Parentage claim text

• Listed as 'Sapa' x 'Oka'.
• Parentage listed as Sapa x Oka; mixed open pollinations.

Derived or downstream cultivar links

• No derived or downstream lineage links yet.

Source-story quotations

• C59-354 Delta Sapa x Oka Mixed open pollinations 1960 Spherical, bluish black, flesh dark red, sweetish and of good quality.University of Saskatchewan fruit introductions 1959-1960, p8
• C59-354 Delta Sapa x Oka Mixed open pollinations 1960 Spherical, bluish black, flesh dark red, sweetish and of good quality.University of Saskatchewan fruit introductions 1959-1960, p8
• C59-354 Delta Sapa x Oka Mixed open pollinations 1960 Spherical, bluish black, flesh dark red, sweetish and of good quality.University of Saskatchewan fruit introductions 1959-1960, p8
• C59-354 Delta Sapa x Oka Mixed open pollinations 1960 Spherical, bluish black, flesh dark red, sweetish and of good quality.University of Saskatchewan fruit introductions 1959-1960, p8

Taxonomy context: No family-tree context surfaced yet.

Related cultivars mentioned in source context