Plum tree named ‘Blackred XXI’

Abstract

The present invention relates to a plum tree and more particularly to a new and distinct variety broadly characterized by a large size, vigorous, hardy, and very productive tree. Being self-unfruitful, the present variety requires cross pollination from an apricot, plum, or interspecific variety that blooms during the mid to late season, such as ‘September Yummy’ plum (U.S. Plant Pat. No. 14,220). The present variety's abundance of blossoms and pollen entices strong bee activity to facilitate pollination. The fruit matures under the ecological conditions described in mid August, with first picking on Aug. 12, 2015, and can hang firm on the tree for up to thirty days. The fruit is medium to large in size, almost entirely black in skin color, clingstone in type, somewhat oblate in shape, red and yellow in flesh color, juicy, very sweet, and excellent in flavor.

We claim: 
     
       1. A new and distinct variety of plum tree,  Prunus salicina , substantially as illustrated and described that is most similar to ‘Blackred XII’ (U.S. Plant Pat. No. 20,892) interspecific tree by being self-unfruitful and by producing fruit that is mostly black in skin color, red and yellow in flesh color, and sweet in flavor, but is distinguished therefrom by blooming about 5 days earlier and by producing fruit that is juicier, that is crisp and melting instead of tough and meaty in texture, that is more heat resistant, and that ripens about fifteen days earlier.