[ 173 ] 



XXXVII. Account of Experiments on the Production of 

 Blue instead of Red Flowers, on the Hydrangea Hortensis; 

 with some Notes on the Propagation and Management of 

 the Plant. By Mr. William Hedges, F. H. S. Gardener 

 to the Earl of Mansfield, at Kenwood. 



Read July 7, 1818. 



Soon after the first introduction of the Hydrangea Hortensis 

 from China into our gardens, some plants of it produced 

 flowers of a blue, instead of a red colour. It was at first 

 thought that the plants which thus differed from the ori- 

 ginal one were a distinct variety ; but as neither the same 

 plants, nor those raised from them, continued to produce 

 blue flowers, it was evident that the change was the effect 

 of a peculiar culture, either accidentally or intentionally 

 used. 



Being much struck with the beauty of the flowers of the 

 new colour, I became very desirous of producing the change 

 myself, and made trial of the different methods which were 

 recommended for the purpose. 



It was at first generally given out, that either common salt, 

 or salt-petreused in small quantities, with ordinary loam, was 

 the cause of the change : these I applied variously, but with- 

 out success ; and I believe it is now well understood, that 

 neither of these ingredients at all contribute, to make the 

 colour of the flowers vary from red to blue. 



