326 



GARDENING. 



July /5, 



Roses. 



QUESTIONS ABOUT ROSES. 



MILDEW, BLACK SPOT, COLD WATER, CLUB 

 ROOT— EEL WORMS. 



Mr. W. Fitzwilliam, Orange, N. J., 

 writes: "Some friends of mine, readers of 

 Gardening, have rose houses situated in 

 a depression known as Orange VaIIe.v. 

 They have been very hadly troubled by 

 mildew on their roses in general, and 

 \yith black spot on their American Beau- 

 ties. We on the hillside are not so 

 troubled. 1. Has the location anything 

 to do with it?" 



Ans. Yes, materially so. In a low, 

 damp location more care will be needed 

 in looking after the ventilation, which is 

 the principal cause of both mildew and 

 black spot. The best preventive of mil- 

 dew is proper ventilation, presumingthat 

 the houses are run at an average temper- 

 ature of 56° ar night, as soon as the 

 thermometer indicates 62° in themoming 

 begin to raise the ventilators and con- 

 tinue to raise them gradually as the tem- 

 perature increases till an abundance of 

 air is circulating all through the green- 

 house; then as soon as the sun begins to 

 lose its power a little, gradually reduce 

 the air till the ventilators are quite closed 

 at a reasonable time in the afternoon. 

 This keeps the plants in a healthy, sturdy 

 condition with thick, leathery leaves, re- 

 sisting mildew. The surest way to get 

 plants affected with mildew is to let the 

 temperature run up to 70° or more, then 

 put on a Ibt of air at once to reduce it. 

 Water, again,' is another factor in the 

 matter of mildew. If the plants are 

 saturated at the roots ai d then run at a 

 high temperature they will produce soft 

 wood and foliage susce])tible to mildew. 

 The sovereign remedy for these troubles 

 is plain, practical, common sense. The 

 same care which a man should take of 

 himself to guard against taking cold, 

 will prevent mildew on plants. Black 

 spot, also a fungoid disease, is not as 

 easily combatted or prevented asmildew, 

 yet a free circulation of air, combined 

 with all other conditions favorable for 

 the best development of the plant will do 

 much to prevent it. One of themost pro- 

 Htic causes of this disease is a close, damp 

 atmosphere, particularly when the plants 

 arc a little too wet at the roots, under 

 such conditions black spot can be pro- 

 duced on the most healthy house of 

 Beauties; letting the plants get a check in 

 any way, particularly in allowing them 

 to get over dry and then giving them an ex- 

 tra heavy watering, will injure the young 

 shoots, and their tops are sure to suft'er 

 in proportion, and black spot to follow. 

 The grower must watch carefully require- 

 ments of his own particular soil and 

 adopt a treatment accordingly, likewise 

 in regard to ventilation. 



2. "They use the West Orange city 

 water, which is very cold in winter. We 

 use cistern water. Is the cold water 

 iniurious in winter?" 



Ans. Vcs, roses are usually grown in a 

 greenhouse with a minimum temperature 

 of .SCi' at night and a maximum of from 

 75' to S.">" during bright days. Now the 

 average mean temperature would proba- 

 bly be about 60° to 6S°. To take a man 

 living in such a temperature and jjlunge 

 him into a bath at say 45° to -1-8° would 

 likelv give him a severe cold or rheuma- 

 tism, if it di<l nothing worse. The same 

 conditions hold good for plants. 



;!. "One of the growers has been 

 troubleil with chi)) root on his roses. We 



use a considerable amount of soot in our 

 compost for roses, also give an occasional 

 topdressing of wood ashes; we are not 

 troubled with club root. Are these the 

 possible causes of our immunity from it?" 



Ans. Yes, materially so. The best pre- 

 ventive is clean, healthy plants to start 

 with. Then select the soil and add a 

 liberal dressing of soot to it when mixing. 

 Never allow the plants to get a check but 

 keep them growing on steadily, and after 

 they are well established give them an oc- 

 casional light dressing of wood ashes, or 

 a watering with lime water if the ashes 

 are not available, only do not overdo it 

 to injure the roots. This pest | the eel 

 worm) is on the increase all over the 

 country, and when once the plants get 

 infested with it there is but little hope for 

 them. Some varieties suffer more than 

 others, and as this ptst is very minute 

 one cannot tell whether it is in the soil 

 unless he examines the natural plants 

 growing it in the field. By examiningthe 

 clover roots growing in the open field the 

 little club nodules if present can be found 

 readily, and where such is the ease you 

 can rest assured that roses grown and 

 forced in that soil will be sure to be 

 affected by club root. The only absolute 

 remedy is to subject every particle of the 

 compost to a very high temperature, say 

 240°, by steam, but this is out of the 

 question with many. John N. May. 



Summit, N. J 



MY ROSES. 



Two plants of the very desirable 

 Japanese Rosa miilti/lora var. Japon- 

 ica were brought to me during the 

 winter of 1887 from London. In October 

 1888 it was transplanted to its present 

 position in Cambridge, Mass., near the 

 Harvard Botanical Garden. After noting 

 its habit a trellis was madeot strong gal- 

 vanized wire netting three feet wide and 

 supported top and bottom Dy heavy 

 wrought iron rods so arranged as to set 

 out about eight inches from the back 

 porch, maskiog the door from the street, 

 and with a southwest exposure. The 

 natural soil is sandy and thin with a pure 

 sand subsoil eighteen feet or more deep. 

 Before planting the rose the old soil was 

 removed to a depth of four or five feet 

 and replaced by a load of rich loam with 

 the old top soil worked in. Every fall it 

 is dressed with a few shovelfuls of cow 

 manure after the ground is first frozen; 

 this dressing is raked off in the spring, 

 the coarse litter separated and the fine 

 returned to the bed after working in with 

 a small hand fork a handful of bone 

 meal. The bush has never been pruned 

 except to cut out the doorway and trim 

 the heps off every spring, which persist 

 over the winter. It was in finest 

 bloom last year, June 14, and in the 

 afternoon a large swarm o( bees was 

 hived off from the fence near by, only a 

 few feet away from the rose. This vear 

 (1895) it was at its best June 12, "and 

 was even finer than it was last year, as a 

 strong shoot was trained last summer 

 high up over the doorway, meeting Hall's 

 honeysuckle trained up the corner post. 

 The flowers are of a brilliant white, and 

 with the bright gold stamens are a hand- 

 some sight. It lasts in good form for a 

 week, filling the air with perfume and 

 attracting swarms of bees that must 

 come four or five miles, as this part of 

 Cambridge is now thickly settled. 



Having a sandy soil I am liberal with 

 water, using the hose frequently through 

 the summer and early fall. All of my 

 Japanese plants suffered severely the i)ast 

 winter except this rose, the Iai)an s ovv- 



down, the honeysuckle was also much 

 damaged. 



Near this rose are the hybrids John 

 Hopper and Paul Neyron that have 

 always thriven. In the back-yard garden 

 we have all the familiar hybrid perpetuals 

 such as Capt. Christy, Magna Charta, 

 Jacqueminot, Baroness Rothschild, Mabel 

 Morrison, and many others, besides Mme. 

 Plantier, the Dawson rose and Gloire 

 Lj'onnaise (which I always protect with 

 straw), and all are pruned back in April. 

 All of these were killed back last winter 

 to eight or ten inches from the ground, 

 but as I cut back quite severely no dam- 

 age has resulted, in fact our roses are 

 larger and finer than ever. 



I spray, first with whale oil soap before 

 the leaf buds break, after that I use Ham- 

 mond's slug shot. The rose bug comes 

 but rarely gets beyond Madame Plantier, 

 which acts as a protector. These bugs 

 are gathered night and morning and 

 crushed between thumb and finger, as 

 dropping them in kerosene takes too 

 much time. [Than dropping them into 

 kerosene nothing can be much simpler or 

 easier; in fact it is the method employed 

 in commercial nurseries where acres of 

 cherry trees in particular are picked to 

 save them trom being almost defoliated 

 by the pests. — Ed.] The only pest on the 

 A'osa multi/Jora is greenfly, which is 

 taken care of by the slug shot and a 

 strong hosing, using full pressuie of the 

 water. 



I have just received second hand from 

 Kew two small plants of Rosa grandi- 

 iiora, do you know it? It is s.aid to be a 

 very old favorite lost to cultivation and 

 now re-discovered. Mine had a few flow- 

 ers, and it is a good thing, but I was sick 

 when it blossomed and did not have the 

 chance to study it. T. N. C. 



Cambridge, Mass. 



[Yes, A'osa grandiRora is grown at Do- 

 soris. See Gardenlng, page 293. Among 

 single roses it is a gem, so full of large, 

 perfect blossoms, and the plant is very 

 hardy. It is generally looked upon as a 

 form of the Scotch rose (Rosa spinosis- 

 sima) and its proper name is Rosa spin- 

 osissima Altaica. The London Gardeners' 

 Chronicle of June 8 referring to it says: 

 "Although described by Lindley as a 

 species, under the name o( Rosa grandi- 

 Hora, and still frequently grown in gar- 

 dens under that name, this rose is now 

 looked upon by botanists as a variety 

 merely of the Scotch rose, Rosa spinos- 

 issima. * ~ There is a group of plants 

 in the Arboretum at Kew covering sev- 

 eral yards, all of which are now thickly 

 crowded with flowers, and make a most 

 charming picture. * * It is a native of 

 the .\ltai Mountains and was introduced 

 in 1S18. '—Ed ] 



NOTES ON TflE CULTURE OF ROSES. 



1. Winter protection. — ^Just before 

 winter sets in — with us the last week of 

 November is usually safe — and when the 

 ground is not at all frozen, I shorten the 

 new growth of the tenderer and less 

 vigorous varieties to about twelve inches, 

 and the others less in proportion as they 

 are more hard}- and free growing. Next 

 I make a mound about each plant some 

 five or six inches in height, the material 

 for which is well rotted compost, two- 

 thirds of which is sod. Lastly I place 

 about this mound, and so far as practical 

 over and among the shortened canes a 

 covering of sods either quite fresh or 

 lifted so recently that they do not break 

 easily. The compost that forms the 

 niouiid is dug in the foUowingspring, and 

 serves n good purpose as fertilizing 



