Triple Crown (Zones 5-9) is valued for producing lots of delicious berries, with some of the berries being jumbo sized. The bushes continue to put out berries from the middle of July through the middle of August, and just a few plants will give you a bountiful harvest. The semi-erect bushes perform best when staked and are resistant to disease. They ripen late in the season, at the end of August or beginning of September. This semi-erect variety has a high yield and is thornless.
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Chester (Zones 5-9) is similarly valued for its bountiful harvests of smaller, semi-sweet fruit. This variety grows quickly and is more resistant to diseases, such as blight, that afflict other blackberries, which aids it in having the highest marketable yields of any blackberry.  It tends to ripen later than most varieties, including Triple Crown, thus allowing for an extended harvest.
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 Twilight (Zones 4-9) is a revolutionary new blackberry variety. The best of eastern and western blackberry genetics has been crossed to create Twilight, a new distinctive, hardy, thornless, semi-erect blackberry variety out of Oregon State. It is known for its outstanding blackberry jam flavor with hints of floral honey notes on large-sized, firm berries with durable, glossy midnight purple skin. Superior in not only flavor and size compared to Chester and Triple Crown but also vigor. High yields are borne on fully thornless semi erect canes in mid-season. Self-fruitful.