726 



HOETICULTUEE 



December 2, 1916 



Xearing the last stages of the 

 growing season the number of hardy 

 perennials suitable for massive color 

 display in the garden is limited. Of 

 course we chiefly rely on ehrj-santhe- 

 mums for late displays. Anemone 

 japonica continues to produce flow- 

 ers more or less freely up to frost. 

 Likewise are Aster grandiflorus, 

 Caryopteris mastacanthus and the 

 arctic daisy, Chrj-santhemum arcti- 

 cum, still available. But for a real 

 solid floral effect there are none of 

 the afore-mentioned that eclipse the 

 eupatoriums, particularly the well 

 known variety Eupatorium coeles- 

 tinum. In general appearance closely 

 resembling the annual ageraturas, its 

 habit of growth is erect and slender, 

 reaching a height of from 1^ to 2 

 feet. The flowers in a cut state 

 possess good lasting qualities and 

 may be used for filling vases. The 

 main reason, however, for granting Eupatorium eoeles- 

 tinum permanent space on our borders is the great 

 abimdance of blossoms at a time when we need them for 

 garden effect. As a flower producer the white species, 

 Eupatorium ageratoides, is equally valuable. Slightly 

 taller, its dense cymes will be found a desirable material 

 in the makeup of various design work of the more in- 

 expensive class. 



Eupatorium purpureum maculatum with its deep 



Eupatorium 



purple flowers is well adapted for the wild flower garden Glenside, Pa. 



Eri'ATORUM rOELESTINUJI. 



or for naturalizing in moist situations of the park. 

 Being natives of our country all the eupatoriums men- 

 tioned in this note require a minimum of care in the 

 garden. A rather light soil, sufficient irrigation and a 

 simiiy exposure are essentials for the development de- 

 picted by our illustration. The common method of propa- 

 gation is by division. Plantations, as a rule, endure the 

 middle Atlantic winters without protection. 



Violet Leaf -Spots 



The question of violet diseases is one which is of im- 

 portance to florists at this time of the year. Most of us 

 have got the violets into the hoiises and many are picking 

 flowers. But it is just now that the success or failure of 

 our violet crop is liable to have its inception. 



Violets, above all plants, are the fussiest in regard to 

 themselves. They must be kept clean. Tliat is, to my 

 mind, the secret of continued success with violets. 

 Leaves and other trash from the plants left lying around 

 on the soil are veritable hot-beds of disease infection. 

 Those leaves would never have left the plants if there had 

 not been something the matter with them. Mr. Florist, 

 would you put your child to bed with a scarlet fever 

 patient ? That's Just what you do when you leave dead 

 foliage and trash around your violet plants. Practice 

 the cleanest culture, and see the difference. 



This article does not make any attempt to treat ex- 

 haustively of violet diseases. Three of the most import- 

 ant leaf-spots only will be taken up. These three are 

 Alternaria Spot, Pliyllosticta Spot, and Cercospora Spot. 

 Altemaria Spot can readily be distinguished from the 

 others. Characteristically the spot is formed in con- 

 centric rings, i. e. the spot seems to be made up of several 

 rings one inside the other. This is considered to be the 

 worst of the leaf-spots of the violet. Many growers have 

 from time to time been forced out of the business by this 

 disease and at best you must expect a continual hard 

 fight with it. This spot is caused by a memer of the 

 I\ingi Imperfecti — Alternaria violae. At first the 

 disease appears as small, greenish-white, round spots. 

 Later, as the spot enlarges, the centers dry up and may 

 fall out. At any rate, the center becomes a pale brown- 

 ish color and is surrounded by a distinct amber-colored 

 margin. Beyond this is an area of tissue of lighter green 



color merging into the green of the leaf. Any portion of 

 the plant, except the roots, may be attacked, but it is 

 most commonly found on the leaves. 



The Pliyllosticta Spot may be identified by the cluster 

 of very minute black or brownish specks in the center of 

 the spot. The spot is whitish averaging one-eighth inch 

 in diameter and the spots often run together and may in- 

 volve the whole leaf. The causal organism is also a mem- 

 ber of the Inmgi Imperfecti known as Phyllosticta violae. 



The Cercospora Spot usually produces a clear whitish 

 or grayish s])ot with a darker center. The fungus caus- 

 ing this spot is a member of the Fungi Imperfecti, too, 

 and is known as Cercospora violae. 



Often it is almost impossible to tell the spots apart 

 especially when two or even the three causal organisms 

 are found in the same spot, as often happens. However, 

 the characteristics given will serve to identify the disease 

 to some extent and only a microscopical examination can 

 make sure of the identity of each. 



Whatever spot the plants may be affected with there 

 is the same treatment. It is useless to try spraying. "An 

 ounce of prevention is worth a pound of cure." Practice 

 clean culture ALWAYS. Wat«r early in the day and 

 only on sunny days. Select strong, healthy vigorous 

 plants when planting. Propagate from clean stock. 

 ■Eenew the soil every season. Finally, keep insects down. 

 They are often a bigger factor in the spread of disease 

 than one would imagine Remember, if you don't let 

 disease gain an entrance, you cannot have an infection. 

 This means that you must pick and destroy all yellow 

 and diseased leaves, plants or plant parts as soon as 

 they appear. 



Amherst, Max 



M). S. WLacU^ 



