AURANTIACEiE. XIV. CITRUS. 



597 



will have made shoots 2 feet long, then harden them before the 

 cold sets in by exposing them to the air by degrees. In Italy the 

 plants are budded at from 2 to 5 feet high on the stem, accord- 

 ing to the intention of the trees ; a bud is commonly inserted on 

 each side of the stock. The Maltese make a sloping section and 

 bud on one side only, which is a much better method than the 

 Italian, as the sloping section becomes covered with bark, which 

 the horizontal ones never do, but a dead stump or rotten hole 

 may be observed during the whole period of their existence. 



Grafting is occasionally resorted to in Italy, and is that most 

 generally adopted in the nurseries at Paris. The stocks when 

 of 2 years growth, and not much thicker than a scion, are cut 

 off and grafted in the whip manner. This manner, as well as 

 approach grafting, is frequently practised in England, as well as 

 another manner of grafting, by taking a slice out of the stock 

 without taking off the head, tying the scion as neatly and firmly 

 as possible, without tongueing it, and claying it over. Mr. John 

 Nairn places his stocks in a hot-bed for a fortnight, in order to 

 rise the sap, that the bark may easily separate from the wood ; 

 the stocks are then cut off about 2 inches above the surface, and 

 a longitudinal incision made with a sharp knife as in budding, 

 separating the bark from the wood on each side. Let the scion, 

 whether in fruit or flower, be cut thin, in a sloping direction, and 

 thrust between the bark and the wood ; it should then be care- 

 fully tied with woollen yarn and clayed, then place a glass of 

 proper size over each, pressing it firmly into the mould to pre- 

 vent the damp from dropping on the scion. These stocks should 

 then be placed on a brisk hot-bed of dung, and in about 6 weeks 

 the glasses may be taken off, and the clay and binding re- 

 moved, but it will be necessary to tie a little damp moss on in 

 lieu of the clay, and keep the glasses on in the heat of the day, 

 removing them at night, when in about 3 weeks they will be 

 fit to put into the greenhouse, where they will be a great orna- 

 ment, being either in flower or fruit. He prefers the Mandarine 

 Orange for this trial, as the fruit is more firmly fixed than in any 

 other sort. 



Mr. Henderson of Woodhall near Hamilton, a superior cul- 

 tivator of the Citrus tribe, considers cuttings as the quickest 

 mode of getting plants. The cuttings should be from !J to 18 

 inches long, taking the lower leaves off to the extent of 5 inches, 

 then cut them right across, make a small incision in an angular 

 direction at the bottom of the cutting, then plant in a pot of 

 sand 5 inches deep, sorting them according to their size, then 

 give them a good watering overhead to settle the sand about 

 them ; he lets them stand a day or two in the shade, then 

 plunges the pots to the brim in a hot-bed, and shades them well 

 until they have struck root. After they are rooted they should be 

 planted separately into pots in a proper compost, place them again 

 in a hot-bed, and shade them for some weeks, then gradually 

 expose them to the air. Cuttings with wood of 2 years old he 

 finds strike as freely as young wood. They may be put in at 

 any time of the year except when the plants are making young 

 shoots. They generally strike in about 6 weeks with a hand- 

 glass over them, in a gentle heat. The Citron strikes easiest, 

 and makes much better stocks for grafting than any other kind. 



By layers. This method is practised both on the continent 

 and in England. In laying, the plants may either be laid down 

 on their sides and laid as stools, or pots may be raised and sup- 

 ported under the branches to be propagated from. Shoots of 1 

 or 2 years growth may be then cut or ringed, and bent into the 

 pot, or drawn through the hole at the bottom, and treated in the 

 usual manner, taking care to supply water with the greatest re- 

 gularity. Shoots layered in March will be fit to separate in 

 September. In general the Citron tribe, like most other fruit 

 trees, do not succeed so well from cuttings or layers as they do 

 by grafting or budding on seedling stocks. 



Compost. At Genoa and Florence they are grown in a strong 

 yellow clay, richly manured ; this is considered by Italian gar- 

 deners to be best suited to the Orange tribe. The French use equal 

 parts of clayey loam, rotten vegetable matter, and half-rotten 

 dung. In the succeeding year they add a portion of decomposed 

 horse-dung, equal to the half of its bulk, turned over 2 or 3 

 times, and many other ingredients, as pigeons' dung and sheep's 

 dung. 



Mr. James Mean (Hort. trans. 2. p. 295.) makes his com- 

 pound as follows : Well rotted cow-dung, 2 or 3 years old, one- 

 fourth, well prepared rotten leaves, 2 or 3 years old, one-half, 

 mellow loam one-fourth, with a small quantity of sand or road- 

 grit added to the compost, which ought not to be sifted too fine. 



Henderson (Cal. hort. mem. 3. p. 302.) takes one part of 

 light brown mould from a piece of ground that has not been 

 cropped or manured for many years, one part of peat earth, two 

 parts of river sand or pit sand, and one part of rotted hot-bed 

 dung, with one part of rotted leaves of trees ; mixes them all 

 well together, so as to form a compost of uniform quality. 



R. Ayres (Hort. trans. 4. p. 310.) uses ten parts of strong 

 turfy loam, seven of pigeons'-dung, seven of good rotten horse- 

 dung, and 10 of old vegetable mould, mixed and prepared a 

 twelvemonth before using. 



Temperature. The standard temperature for the Citrus tribe 

 is 48", but in the growing season they require at least 10 degrees 

 higher to force them to produce luxuriant shoots, but the air of 

 the house should never be allowed to fall under 40. Although 

 the Orange will endure a severe degree of cold for a few hours 

 without injury, yet, as Mean has observed, the leaves once in- 

 jured, the trees will require 3 years to recover their appearance. 

 Ayres never suffers his Orangery to be heated above 50 by fire, 

 until the end of February, when the trees show blossom ; it is 

 increased to 55, but never allowed to exceed 60 by sun heat, 

 the excess of which he checks by the admission of air till the 

 early part of June, when he begins to force the trees by keeping 

 the heat in the house up as near as possible to 75. For, he 

 says, that neither Citrons, Oranges, Lemons, or Limes, can be 

 grown fine and good without less heat (Hort. trans. 4. p. 311.). 

 The Orange, Humboldt observes (De Distrib. Plant. 158.), 

 which requires an average temperature of 64 degrees, will bear 

 a very great degree of cold, if continued only for a short time. 

 Dr. Sicklers says, " it is remarkable how much cold and snow 

 the common Lemons and Oranges will bear at Rome, provided 

 they are planted in a sheltered situation, not much exposed to 

 the sun. He saw at Monte Pincio 3 standard trees in the open 

 ground heavily covered with snow for more than a week. The 

 green leaves, but still more the golden fruit, looked singular and 

 beautiful amidst the snow. Neither fruit nor leaves had suf- 

 fered, being in a sheltered place, while those that were exposed 

 to the sun turned black and died, rendering the whole tree at 

 once sickly. This proves that it is more the sudden transition of 

 heat to cold or cold to heat, than the degree of either which de- 

 stroys vegetation, as it appears that the snow had been thawed 

 gradually from off these trees, and more by the temperature of 

 the atmosphere than by the direct rays of the sun. Oranges 

 will stand the climate of Devonshire and Cornwall, and perhaps 

 the south of Ireland, in the open air in sheltered situations. All 

 the species endure the open air at Nice, Genoa, and Naples ; but 

 at Florence and Milan, and often at Rome, they require protec- 

 tion during winter by placing the trees in conservatories, or 

 under sheds. But the finest orange orchards are in the vicinity 

 of Genoa. 



Air. Orange trees require a large share of air when the 

 weather is favourable ; the prevention of damp is as essential 

 to the perfection of the plants as the exclusion of cold. Where 

 these trees are kept in old-fashioned opaque-roofed green- 



