for ^ovember, 1920 



379 



country to another. The failure of Sweet Peas to flower m the 

 West Indies may be due to an incompatibiHty between the length 

 of day there and that to which this plant is naturally attuned, and 

 the change or maintenance of season of flowering of introduced 

 plants may be due to a like cause. That the failure of some trop- 

 ical or sub-tropical plants to blossom in countries of temperate 

 climate would appear, from the authors' observations on the be- 

 havior of Phaseolus vulgaris, to be attributable to a like cause. 

 For this plant, when grown in the open in the latitude of Wash- 

 ington generally fails to blossom before it is cut down by autumn 

 frosts ; whereas if taken up and sheltered in a greenhouse it pro- 

 duces flowers freely during the short winter days. When the 

 days were experimentally limited each to seven hours P. vulgaris 

 was found to blcom in 28 days, and to ripen its seed pods a 

 month later ; albeit that when grown in the open it could not 

 blossom liefore October 11. 109 days after germination; it is as 

 though the plant has to wait until the days arc short enough in 

 order to find release from the vegetative stage and to pass mto 

 the reproductive i)hase. According to the views developed in this 

 interesting contribution to our understanding of seed time and 

 harvest, plants range themselves in three categories : short day 

 plants, which in such a climate as ours must flower either in 

 Autumn or in Spring, long day plants which are summer tlowerers. 

 and ever-flowering or perpetuals. for which the limits of suitable 

 days' lengths are" so wide as to free them apparently from the 

 restraint which controls the blossom time of the plants of the first 

 two categories, .\lthough the cautious will no doubt prefer to 

 await the result of further experiments, yet it cannot be doubted 

 but that JSIessrs. Garner and Allard have opened up an extremely 

 interesting line of inquiry, have shed a new li.ght on many obscure 

 phenomena exhibited by the blossoming plants and have elucidated 

 the mode whereby plants conform to the divine behest — "so long 

 as the earth endureth. seed time and harvest shall not fail." — 

 Tlic Gardoii-rs' Chronicle (British). 



quently any severe pruning in Winter will limit the display of 

 blossoms. '.\11 that is needed is to remove any weak or exhausted 

 wood that is not likely to flower, but be sure and retain the vig- 

 orous shoots, as they will yield the greatest wealth of blossoms. 

 Clematis Jackmani, on the other hand, forms shoots of consider- 

 able length before they flower, so that they may during the Winter 

 or early Spring be pruned back to good strong buds and any 

 weak or exhausted shoots cut out. Clematis Duchess of Edin- 

 burgh will require little pruning, all that is needed being the thin- 

 ning out of any weak growth during the Winter when dormant. 

 Clematis indi-cisa lobala. the evergreen species that requires the 

 protection of a greenhouse, blooms early in the Spring, and all 

 the pruning needed must he done directly the blooming season is 

 past. Where it is necessary, the vigorous shoots may be short- 

 ened back to good strong eyes and the weak ones thinned out. 

 but in the case of this Clematis, as with the others, the less prun- 

 ing that is indulged in. unless in some exceptionable cases, the 

 greater will he the display of blossoms, though such a free 

 grower as C. Jackmani may sometimes form too dense a tangle 

 unless pruned back somewhat during the Winter before the buds 

 push into growth. — Gardening Illustrated. 



THE CLEMATIS FOR NATURAL EFFECT 



Xo genus of plants furnishes us with such a varied assortment 

 of handsome flowering subjects of climbing habit as do the 

 Clematises. These, though always beautiful when in blossom, are 

 never seen to such advantage as when permitted to ramble at will 

 through and over other living growth. It should be remembered 

 that, for artistic efifect. the more freely climbing plants grew the 

 better, and tliat most species of Clematis may be allowed un- 

 restrained freedom with the happiest results. The large-flowered 

 Clematises provide a charming picture when clambering among 

 the branches of shrubs and trees. It is often thought that these 

 large-flowered Clematises of the lanuginosa, fratcns, florida, and 

 Jackmani sections are of too delicate constitution to admit of 

 theit being planted in close proximity to trees and shrubs possess- 

 ing a vigorous habit of growth, but such is far from being the 

 case, even such a rapacious neighbor as a Laurel hedge failing 

 to affect their vitality and being garlanded in the summer months 

 with trails of widespread stars. 



The Clematis, in common 'u-ith all climliers. ^bnuM. at the start, 

 be afforded a deep and rich root-run. but when the plant has 

 once become established it is enabled to hold its own against the 

 most greedy associates. Large-flowered Clematises have, unfor- 

 tunately, a habit of dying off suddenly when apparently in the best 

 of health, shoots that are one day green and vigorous being found 

 withered on the succeeding day. This failing, which has been 

 styled the "Clematis disease," has been ascribed to a variety of 

 causes, such as the widely-employed system of graftin.g, exposure 

 of the stems to the sun. excess of water at the root, and the after- 

 effect of injury by frost during the Winter. Init. up to the present, 

 no authoritati\e decision on the subject has been arrived at. That 

 the evil of grafting, while, doubtless, tending to weaken the plant, 

 is not the sole reason of dying ofif is proved by the fact that speci- 

 mens raised from layers and seed sometimes fail in the same 

 manner, but the three other assigned cau.ses — namely, excess of 

 moisture, scorching of the stem, and injury by frost — are avoided 

 by growing the plants with other subjects whose roots absorb any 

 overplus of water, and whose growths shield from damage by sun 

 or frost. Thus it is that in large-flowered Clematises grown over 

 shrubs or in company with other climbers the "disease" rs rarelv 

 seen. 



The pruning required by the dififercnt kinds of Clematis will 

 to a great extent depend upon the position in which they are 

 growing, for if festooning any extensive support, such as neigh- 

 boring trees, or clothing an arbor. little if any pruning will be 

 required, while, on the other hand, if trained to a wall where 

 space is limited, pruning is absolutely necessary in. order to keep 

 the specimen within bounds. Clemaiis montana flowers from the 

 young shoots directly they push from the old wood, and consc- 



A LESSON ON PLANT PHYSIOLOGY 



[L iintiinied from pifge 377 I 

 by the prevention of seeding, and even in the case of many 

 annuals, especially with sweet peas, which soon perish if allowed 

 to seed but which will continue to bloom throughout the Summer 

 if the flowers are persistently picked. The same is true with the 

 majority of perennials, and even with those perennial species, like 

 Iris, Peonies, and bulbous subjects, flower stems should be cut 

 as soon as the bloom falls. It may be taken as a general rule that 

 the more flowers we cut the more we 'have. 



The prevention of seed formation can, too, with advantage, be 

 carried out among shrubs, especially with those forming their 

 flower-buds the year before they bloom ; examples of the latter 

 are seen in the Rhododendron and Syringa (Lilac). 



The same principle applies in connection with many vegetable 

 crops. Whether the produce is required at the time or not. all 

 peas, beans, cucumbers, etc., should be gathered as ready, for the 

 total yield will be considerably increased and the bearing of the 

 plants much prolonged 1)y gathering before the ripening process 

 begins. 



Overbearing of fruit is frequently harmful, and certain varieties 

 of some cultivated fruits, as apples, pears, plums and peaches, 

 may in some seasons set such a full crop which will, if it is all 

 allowed to mature, cause such an undue amount of their reserve 

 food to be devoted to fruit pr'iduction as to result in greatly en- 

 feebling the trees : in fact, instances have been known where a 

 young tree has been allowed to bear such a heavy crop of fruit 

 that death has resulted. It is always a wise procedure to thin 

 a heavy setting of fruit before it has made much growth, as this 

 will save the tree from undue exhaustion, and improve the size 

 and quality of that allowed to remain. -\Iso, in the case of apples 

 especially, thinning tends to increase the possibility of an average 

 crop the followin.g year, instead of, in the case of a tree ex- 

 hausted by overhearing, none at all. 



In connection with fodder crops, grass and other things in- 

 tended for feeding purposes should not be cut in such ripe con- 

 dition as is frequently the case; their feeding value is .greatly 

 reduced when seed is permitted to form or ripen before cutting, 

 and also more plant food is tliereliy taken out of the soil for no 

 good purpose. 



THE TREE 



I lo\e thee when thy swelling buds appear. 

 •And one by one their tender leaves unfold. 

 .\s if they knew that warmer suns were near, 

 Xor longer sought to hide from Winter's cold ; 

 .\nd when with darker growth thy leaves are seen 

 To veil fri-ni view the early robin's nest. 

 I love to lie beneath thy waving screen. 



And when the .\utumn winds have stripped thee bare. 

 And round thee lies the smooth, untrodden snow. 

 When naught is thine that made thee once so fair, 

 I love to watch thy shadowy form below, 

 .•\nd through thy leafless arms to look above 

 On stars that brighter beam when most we need their love. 



— ^JoxES Very. 



