TO 



PETREA VOLUBILIS. 



public. The plant ought to be spurred like a grape vine, in order to get spurs 

 distributed all over the plant ; the flowers being produced on spurs of the 

 previous year's growth. I ought to remark, however, that the pruning of all 

 ornamental plants, whether climbers or otherwise, must be guided, in a measure, 

 by circumstances. The Petrea may be trained over a trellis, up a rafter, or 

 round four or five sticks in a pot ; or it may be formed into the shape of a 

 standard rose, by disbudding the stem up to three or four feet, leaving two joints 

 at the top, and stopping the leading shoots: these two joints being each 

 furnished with two eyes, will throw out four shoots ; these shoots ought to be 

 allowed every indulgence the first season, and to be pruned back according to 

 their strength the following season, just as they are beginning to grow. The 

 formation of a regular round head being once obtained, the plant must be 

 subjected to a more severe system of pruning; the leading shoots must be 

 stopped at every second joint, in order to make them produce laterals all over 

 the shoots : these lateral shoots are stopped at the third or fourth joints (or even 

 shorter if they are not vigorous) and will then become flowering spurs. 



When the plant is trained up a rafter, the leading shoot should not be 

 stopped if the plant throws out laterals at every joint. 



If good friable loam can be procured for this and most of the woody climbers, 

 they will be found to grow and flower more freely in it than when mixed with 

 one-third peat, the universal compost of writers, though given up long since by 

 the best cultivators. If the loam is too stiff, or is apt to get hard in the pots, a 

 little peat is absolutely necessary to keep it open ; but in nine cases out of ten a 

 layer of peat and loam on the top of the pot is quite sufficient. The Petrea 

 grows freely from cuttings of the young or old wood, if placed in a brisk bottom 

 heat under a hand-glass. 



The generic name Petrea was given to this plant by Houston, its discoverer, 

 in honour of Robert James Lord Petre, a great patron of botany, who died of 

 small-pox, when a young man, about the year 1742. Peter Collinson, in a letter 

 to Linnaeus, published by the late Sir J. E. Smith, in the Linnean correspondence, 

 speaks of the death of this young nobleman, as the greatest loss that botany or 

 gardening ever felt in this island. 



The specific name volubilis refers to its climbing habit. 



