JOURNAL OP HOETICULTUKE AND COTTAGE GABDENER. 



[ AprU 2, 18(e. 



aify manurecl, shading from bright sunshine, and keeping 

 fl»e rhizomes in a stove temperature during winter. — J. A., 

 Walihouse Gardens. 



MERITS AND DEFECTS OF CENTAUREA 

 CANDIDISSIMA. 



I CAK fully confirm ^Yhat Mr. Record states with respect to 

 ^e disease in Centaurea eandidissima (see page 219), and, 

 imdesd, can go a step further, and say that with me the plant 

 Jjas shown disease when in a single row. The first symptoms 

 o£ the disease appeared here in 1804, and the plants were so 

 xarBeh afiected by it in the following year that I have since 

 gtfwrB the Centaurea but little. The tips of the leaves were 

 MTimpled and decayed, and this decay continued until but 

 little of the plant was left, and it was, of course, useless for 

 ormamental purposes. Single plants are sometimes attacked 

 m ft similar mauner, but not so generally as those planted 

 IB lines or masses. This evil, coupled with the fact that the 

 J>i&nt does not, under the best management, increase so quickly 

 as many others, will go far to keep it from being so much used 

 as it would be did such drawbacks not exist, for when it does 

 wsm nothing can be handsomer. The gracefully recurved 

 Iserea when fully developed, and what is of more consequence 

 tiun all, its paucity of flower stems, give it a decided advantage 

 •Ter all other plants of its class when it is well grown. I 

 tniciM not have said this much in favour of the Centaurea had 

 Cmeraria maritima been less apt to run to seed ; but its ten- 

 jleiaey to do so, and the disfigurement its foliage receives if any 

 attempt is made to prevent seeding, greatly detract from its 

 beaoty. For my own part I confess being unable to overcome 

 sto tendency to run to seed. The hardiness of the two plants 

 ia sbont equal, but the Cineraria is much more easily propa- 

 gated,, or rather it affords cuttings in greater number, and these 

 atriko freely enough when allowed time. 



Another great disadvantage of the Centaurea is its liability- 

 to die when taken up in autumn. lu most cases we have lost 

 JjslSy three-fourths of the plants so taken up between the 

 period of their removal from the ground and the following 

 Maieli, the consequence being that few cuttings were to be ob- 

 ttijsed in spring, although any that can be had then strike very 

 fnely. One or two seasons I left some old plants in the beds, 

 fctttths disease in one instance, and the severity of the winter 

 IB another, were fatal to them; but I see that four plants 

 Wbi^ had formed the centres of four elevated beds, and which 

 were left out in the autumn of last year, are as fresh as in 

 October, and each plant will furnish a number of cuttings. 

 Shis would seem to indicate the propriety of trying to grow a 

 few ptauts in some sheltered dry spot, on purpose to propagate 

 Suraa in spring. Most likely in a dry stony soil plants would 

 ke preserved through the winter with very little protection ; 

 fliOBe I have just referred to had none. I imagine that this 

 Jtlant in its natural state must occupy a high and dry situation, 

 J06»ibly some rocky promontory or similar position, as the 

 nnoist stagnant air of our forcing houses seems fatal to it in 

 wSiiter, and it is not improbable but more losses have been 

 ffneteined in consequence of the plant being too much coddled 

 Jbm by a contraify course. 



Astothe respective merits of spriug and autumn propaga- 

 tioB, I can offer but little opinion. When cuttings can be had 

 and pnt in during the spring, roots are formed more speedily 

 ihoB in autumn; but my experience would say. Try both 

 flKDS. If cuttings can be had in September, take them off 

 and insert them in boxes or pans in an airy place, but not in 

 &• full sun ; artificial heat, I think, is not wanted at this 

 ffiiae. One precaution in putting in the cuttings ought to be 

 attietly attended to, and tliat is, to be sure not to insert the 

 ! BO deeply as to bury the heart, otherwise the cutting 

 hea. I believe that more losses occur in this way than 

 . people suppose. When the dull days of autumn fairly 

 let the cuttings have all the sun and light possible ; a 

 near the glass, where water but seldom reaches them, 

 tetaae of the bast places ; but so capricious is this plant that 

 ■Itbosgh sometimes almost every cutting will grow, at times 

 lb* failure will be almost total. In spring there is a gi-eater 

 OWta iaty of cuttings becoming plants, but the number of 

 Wtlii gs at this time is far from plentiful, growth during the 

 VOttsF being slow. I am certainly disposed in future to see 

 Wbat esn be done by letting a few plants remain out of doors 

 aBwimter in some suitable spot. 



Ssnng already remarked that the Centaurea is not so apt to 



run to flower as the Cineraria, it will, of course, be under 

 stood that it produces seed less plentifully, so that we cannot 

 thus increase it to any great extent ; but probably when we treat 

 it the same as the bedding Calceolaria, we may have it in 

 greater abundance. For the last three years I have thus treated 

 Centaurea gymnocarpa, and with perfect success, at least so far 

 as propagation is concerned, for the plant is a more robust 

 gi'ower, and furnishes cuttings in abundance, and these put 

 into a cold pit in sandy soil by the middle of October, or earlier, 

 make good plants by the usual planting-out time, the beginning 

 of May. The tendency, however, of plants so raised to run to 

 seed, and their furnishing little or no foliage, are great dis- 

 advantages ; otherwise the free growth of this plant, and its 

 graceful habit, render it superior to C. eandidissima, although 

 its foliage is not so white. 



Cutting off the flower stems will not prevent Centaurea 

 gymnocarpa running to seed, but plants from cuttings struck 

 in spring are not so apt to do so as those from autumn-struck 

 cuttings, and with me young plants of this Centaurea running 

 to seed early in the season are quite useless, and dwindle off 

 or die. Cineraria maritima, although persistently producing 

 flower stems notwithstanding repeated cutting-off, does not 

 die under the operation, neither does flowering occasion the 

 death of the plant, as in the case of Centaurea gymnocarpa, 

 which in this respect somewhat resembles a biennial. 



Probably the most useful plant of the three is the Cineraria 

 maritima, and it is also most easUy multiplied. Its greatest 

 drawback would appear to be the late period of the season at 

 which cuttings arrive at a proper size ; in all other respects this 

 plant may be said to possess advantages which the others do 

 not. Growers who have been more successful with Centaurea 

 eandidissima may think differently, and when that plant is 

 free from disease, and can be propagated as easily in equal 

 number, I will readily give it the palm, but hitherto in most 

 places I am acquainted with this has not been the case. The 

 different views taken by those who speak of its propagation are 

 so conflicting, that it is reasonable to suppose that even the 

 most successful growers of it have now and then their reverses 

 and disappointments. — J. Kobson. 



NEW GLASS STRUCTURES FOR GROWING 

 FRUIT AND FLOWERS. 



The treatment (referred to in my remarks in page 238), which 

 I conceived necessary for Peaches, Nectarines, and Apricots, 

 rendered, as I supposed, half-hardy by impairment of con- 

 stitution, was that of the valetudinarian. I screened them from 

 cold cutting winds, at the same time giving them sufficient air 

 at night, as well as in the day, keeping as near nature as pos- 

 sible. I luckily had some of these trees growing by them- 

 selves, offering fair opportunities for being experimented on. I 

 adopted a simple but effectual mode of screening these trees, 

 thus preventing the heat generated by the earth and sun from 

 being rapidly carried away. This protection consisted in 

 driving bars (grooved on the opposite sides, and previously 

 boiled in creosote), into the earth at stated distances. Into 

 these grooves 21-oz. sheet glass, 20 inches by 15 inches, was 

 slipped, the screens thus formed being from 5 to 10 feet in 

 height, of a diameter according to the size of the tree to be 

 enclosed. A space was left for a door, and a close net was 

 thrown over the top to keep off froet. 



This plan answered so well, that in the course of ten days a 

 most marked effect was produced on the foUage ; from the ex- 

 posure to light on all sides, the leaves became of a dark green, 

 and very large, also free from anything like blotches. The 

 fruit set thickly, and continued to grow without any drawback, 

 until it thoroughly ripened. . The Jefferson Plums, three dozen 

 on one tree, and four dozen on the other, were most delicious, 

 and not deformed by insects. A gardener who came from 

 Wolverhampton on purpose to see these experiments, said, 

 "If these are Plums, I never tasted a Plum before." The 

 flavour of the Peaches was brisk and piquant, different from 

 those shut up at night, or even those ripened on walls. One 

 thing which astonished me most, was the perfect ventilation. 

 As there was no opening, except at the top, it might hare 

 been imagined the airvrould become stagnant; but insteadoi 

 this it was in constant motion. The average temperature in- 

 side these screens was from 10' to 15° Fahrenheit above that 

 of the external air. The hotter the air the more rapid the 

 circulation, the heated air ascending at the sides, and the cold 

 air falUng in the centre. If the soil be covered with coal asbeS 



