This section is from the book "Commercial Gardening Vol3", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
This hybrid between the Red Raspberry and the Blackberry (named after the American Judge Logan) is now well known, but it cannot be said that it has yet " caught on" with the market-garden community to any great extent. As it grows vigorously in almost any soil, and requires but very little attention, there is no reason why it should not be planted in waste corners of the garden where there is at least abundance of sunshine, for it loves the light. The white starry flowers appear at the end of April and early in May, from eight to twelve in a loose panicle on the shoots that spring from last season's growths - these often attaining a length of 12-16 ft. The plants resemble the Blackberry more than the Raspberry in appearance of flowers and foliage, but the fruits are much larger than those of either and quite distinct in flavour. Although perhaps a little too acidulous for dessert, there is no doubt as to their value for preserves, and they ought to find a ready sale among jam makers. Under good conditions one plant will produce from 5 to 10 lb. of fruit. (See Coloured Plate.)
Cultural treatment consists in giving a dressing of well-rotted manure in the winter when the soil is being forked up lightly, and in cutting out all the dead canes that fruited of the last year's growth. The best of the young shoots should be retained and tied to stakes or fences, and the tops should be shortened back a few inches, but not severely, as in the case of Raspberries.