Jewel raspberry plants have biennial canes or stems and perennial roots. The canes grow from root suckers and produce vegetative growth during the first year of growth and fruit in the second year. The first year canes are referred to as primocanes and the second year canes are called floricanes. Plants have a mature height of about 10 feet, growing into large, dense 3 1/2-foot-wide shrubs.
The fruit grows on vigorously growing plants with arching canes that root at the stem tips. Jewel raspberries are full-flavored, firm and glossy. The variety is among the mid-season raspberries. The fruit is ready to harvest between late June and early July. Though jewel raspberries are flavorful and large in size, they have a short harvesting period. Black raspberries like jewel are generally less cold hardy than the red raspberries.
Raspberries are ready to harvest when the fruit is easy to separate from the core or receptacle. Check the fruit frequently and harvest immediately upon ripening, as raspberries are among the most perishable of fruits and spoil rapidly. Refrigerate fruit after harvest to help maintain freshness for three to seven days. Very ripe berries with the likelihood of spoilage prior to use may be frozen for future use.
Prune jewel raspberry plants regularly to maintain plant health, reduce chances of disease and improve fruit yield. Pruning is done three times a year in spring, summer and after fruiting. Cut back the lateral branches to 8 to 10 inches in mid March. During the second pruning, remove 2 to 3 inches of the new shoots during the summer. The third pruning is done following fruit harvest where the canes that produced fruit are cut to the ground.