512 



JOURNAL OF HOETICULTUEE AND COTTAGE GARDENER. 



[ Decembor 29, 1863. 



the most suitable. In this he agrees with most Rose- 

 growers, as he does ylso on the vahie of the Manetti stock. 

 His observ.ations on pruning are especially valuable. We 

 know so well what is too olten done. " I should like my 

 Roses pruned !" In comes frardener with his great pnming- 

 knife ; never asks what the Koses are — like quack medicines, 

 the same treatment does for all, and the consequence is 

 failure in too many cases. Now Mr. Cranston takes the 

 various sections, shows how and when they are to be pruned, 

 and the best form to be given to the plant. The diseases of 

 the Rose .lud the insects injui-ious to it are also described, 

 although the most destructive of the pests, the lai-va of the 

 Tortrix — the " worm i' the bud" — is omitted. 



It would be impossible for us to give anything like an 

 idea of the amount of inform.ation contained in this valuable 

 manual ; and we have, therefore, only to recommend all 

 who are desu-ous of successfully cidtivating the Rose to 

 seek for the knowledge fi'om one so well capable of giving 

 it as Mr. Cranston. 



OBTAmiNG BLUE-FLO WEEED HYDEANGEAS. 



In yoiu" answer to a correspondent, " J. W. L.," page 458, 

 on obtaining blue-flowering Hydrangeas, yoix quote from an 

 article on that subject l.ij' the late Mr. Beaton, which shows 

 the wonderful sagacity of that person on that as on all sub- 

 jects upon which he i\Tote; and though from his writings I 

 coiild never make out that he had .any great practical know- 

 ledge of chemistry, still, whenever required he did not fail 

 to indicate that he did possess a certain amount of knovif- 

 Icdge on that as on most other subjects connected with gar- 

 dening, and it will be long ere we see his like again, or one 

 to assume the pen v.iiich he has for ever laid down. 



I only take up mine to state what experience I have had 

 on the subject of blue-flowering Hydrangeas, hoping it may 

 be of use to some young aspirant to a knowledge of the 

 chemistry of the subject. 



Upwards of twenty years ago this question was much 

 agitated in the various horticultural publications, and 

 various were the methods proposed to cause the HycU-angea 

 flowers to become blue. At that time I was always ready 

 to try any suggestion which took my attention or excited 

 my curiosity, and the production of blue-flowered Hydi-au- 

 geas was one of them. 



I have tried iron filings, iiisted iron, and soils of all 

 mixtiu'es and coloiu-s, and was only successful with one, and 

 that was Norwood loam. It was brought to the place for 

 other potting purposes, and I used some of it for the Hy- 

 drangeas, and certainly the flowers became blue ; but on 

 using again the loam from the same heap the following year 

 not one became blue, neither by that loam uor any other 

 which I used. 



A longer study and greater interest in the science of 

 chemistry has often brought back to my recollection the 

 circumstance of the Norwood loam making the Hydi'angea 

 flowers blue one year and failing the next, and I have often 

 intended to investigate the subject, but otlier avocations 

 have hitherto prevented me from making further experi- 

 ments. 



I shall, however, state, what I understand to be the cause 

 of the change, and perhaps your correspondent may jjut it 

 to the test of experiment, and let us know the result. The 

 loam had been newly dug out of a deep pit, and used by 

 myself at once. Although I never tried whether the loam 

 contained iron or not in its composition, I think there can 

 be no doubt but that it did. irom its colour and consistency, 

 and I am disposed to think that the iron in it, before ex- 

 posure to the air, v.-as in the state of a protoxide, and 

 soluble in water, and in that state entering into the plant, 

 might cause it to turn blue, while after exposure to the aii" 

 the protoxide, Fe O, would bo converted into the i^eroxide, 

 Fe» O3, bj' combining with other two atoms or equivalents 

 of oxygen, and being insoluble in water would prevent the 

 iron from entering into the juices of the plant in sufficient 

 quantity to cause the blue. It is also remarkal^le that Mr. 

 Beaton says, " that cuttings struck in August failed to 

 change colour though grown in iron filings," just, I think, 

 because the ii'on Vv'as only iu the state of a i^eroxide, and 

 insoluble. He also says, " that by growing them in strong 



yellow loam with a sixth of iron filings, nine out of ten wiU 

 produce blue flowers." Now, I apprehend the reason of 

 that is, that the yellow loam might have contained the iron 

 in the state of the protoxide, even in smaller proportion, and 

 hence the blue. 



It is well known that the colour of nearly all yellow SOU.? 

 is caused by the presence of iron in their composition ; and 

 the change which takes place in those soils when turned up 

 to the atmosphere from the pale yellow to the reddish-brown, 

 is caused by the conversion of the protoxide of iron iato 

 the peroxide. If the former is present in any great quantity 

 there .are few plants that will grow in it. It acts as a 

 poison, but when turned up and exposed to the influence of 

 the atmosphere, it shortly becomes food to the plant. 



If those soils which naturally produce the blue Hy di'angeas 

 were subjected to analysis it might set the matter at rest ; 

 and should any one see this who has Hydi-angeas which 

 produce blue liowers naturally, and forwai'd by post, in a 

 close tin box, about a fourth of an ounce of the soil in which. 

 the pliints grow to my addi-ess, I will be able to ascertain 

 in what state the iron is present in it. The soil must be 

 taken from where the points of the roots are. Or, if any one 

 living at Norwood would forward to me the same quantity 

 dug from the solid, 2 i'eet deep, I would like very well to 

 ascertain if I .am right ia my conjecture, and I will not fail 

 to let the result be known in this Journal. 



There is abundance of the sod here having the iron in 

 the state of a protoxide. All the subsoil is so, and so poor 

 that I do not think that were I to try I coiUd make a Hy- 

 drangea flower in it. 



If "J. W. L." tries the iron filings I hope he will let us 

 know the result. Although I was not successful with the 

 rust, others may be so. I am strongly of opinion that plants 

 possess a great power themselves, when their roots come m. 

 contact with the inorganic matters in the sod, of decomposing- 

 the sod, and taking up what they requh'e, and not so much 

 by the chemical changes which we know arc ever going on 

 in the soil. Professor Way's celebrated exi)eriments prove 

 that water is not the carrier of food to the plants, only the 

 medium, like the soil, in this important function. Both 

 are necessary, but they must be in their proper proportions ; 

 and tliough the iron in the sod is not iu a soluble state, 

 neither is it soluble by adding rust, still the plant may 

 obtain it iu thiat state from the soil when m abundance, 

 and so cause the Ijlue colom- of the Hydrangea. 



All chemists are awai-e that when the ferrocyanide of 

 potassium is added to a solution of iron it makes a beautiful 

 blue colour v.ith a considerable precipitate : therefore I do 

 not see that it is difficult to conceive that a plant may have 

 the power of making similar changes from the elements of 

 the soil in which it grows, and so change its colour.. — Alex. 

 Sheakek, Yester Gardens. 



HOLLAND HOUSE. 

 The Seat of Lady Holland. 



This is entered on the rigUt through a splendid pair of 

 gates from the high road between Kensington and Hammer- 

 smith, and the beautiful old mansion is seen through the 

 trees seated high in the park, and it is apiproached by an 

 avenue of Elm trees. The chief parts of this structure were 

 raised by Sir Walter Cope in the year 1607. To the south 

 is the large scjuare bowling-green terrace bounded by balus- 

 trades, lately adorned with flowers iu vases of Malta stone, 

 and four large Orange trees ai'e in li'ont with a large basin- 

 fountain iu the centre. To the east frout is the flower 

 g;U'deu, a rich parterre, and of a beautiful pattern. The 

 diamond-shaped beds and circles of tiie chain-beds were 

 chiefly planted with different varieties of Verbenas aiT.anged 

 according to then- colours and shades to give a harmonious 

 effect. 



Although the experimental inquiries of Sir Isaac Ncivton, 

 Sir David Brewster, and other eminent philosophers have 

 proved that the j^henonema of colours are regiilated in 

 theh' combination by irrefragable lnws of harmony, yet the 

 error of considering the arranging of coloui-s as a matter of 

 fancy merely is very prevalent. Many have likings for, and 

 antipathies to, particular hues — all have their partialities 

 to particular styles of colouring, some delighting in the gay 



