570 THE GARDENER. [Dec. 



and bottom temperature is the surest means of preventing damping off, which 

 disease is indeed the result of a sluggish action in the plant or impaired vital 

 energy. In early forcing, however, this practice must be modified considerably. 

 During the dark days of February and March a high bottom-heat will compel the 

 plants to grow ; but the pale sickly foliage which they make under such cir- 

 cumstances will perish before the first blink of the April sun. In early forcing, 

 therefore, of the Melon, it is much better during dull sunless weather, by a 

 lowered top and bottom temperature, to keep the plants still, and make hay 

 while the sun shines. Mere elongation of the tissue, the result of hard forcing 

 during the early part of the year, may be growth, but it is not progress, for in 

 the end neither time nor quality will be gained. 



With regard to bottom-heat generally, it may be laid down as a maxim, based 

 upon experience, that all plants, from Pines to Potatoes, require a root -tem- 

 perature equal to the mean temperature necessary for the development of the 

 branches. I do not mean to say, of course, that we cannot succeed partially 

 unless these conditions are strictly fulfilled, but I say that the nearer this is accom- 

 plished, our success will be the greater. This is proved by everyday experience ; 

 and the question is not whether bottom-heat is necessary, as has been argued at 

 great length in the case of Vines, for instance, but how is it to be applied ? That 

 Vines will not only stand, but be immensely benefited by, a high root-temperature, 

 has been proved often enough — witness its efi'ects in the forcing of pot Vines. 

 We started some last November, at the same time as our early vinery ; the fruit 

 on these is now ripe, but the early house will not be ready for five weeks. The 

 pot Vines were plunged in a bed of leaves the most of their time ; in the other 

 case the roots of the Vines are in an outside border. The inference is plain. 

 Yet we have at various times been astonished with accounts of Grapes being 

 ripened by the beginning of May, though the roots of the Vines had never enjoyed 

 more than a winter temperature. I am afraid such feats must be put down 

 among the things that are not dreamt of in our philosophy, and be reserved for 

 some future Lindley to unravel. 



My convictions regarding the importance of heated borders are unshaken, and 

 have been forced upon me by experience of the most conclusive description, though 

 I am not an advocate of some modes of heating. We have two vineries here, 

 which I will for convenience call No. 1 and No. 2. No. 1 is an old vinery, des- 

 tined to be taken down in its turn and rebuilt, and which has for the last four 

 years been pressed into service as an early house. The roots of the Vines are all 

 outside. The border is about 4 feet deep, or i-ather more, and has apparently 

 never been drained in any way underneath^ — for the reason, perhaps, that the sub- 

 soil here is dry and rocky; and in anticipation of having to renew the border 

 entirely before long and replant, we have never disturbed it. No. 2 is a new 

 vinery, but the Vines are about forty or fifty years of age, and in excellent health; 

 their roots are all outside also, but the border in this case, having seemingly 

 been made or renewed at a later period, is thoroughly drained, the bottom being 

 covered with about 9 inches of rubble, and intersected with good drains, 4 feet 

 apart. In addition to this, as the house was intended to be pushed forward for 

 early work while No. 1 was being rebuilt, we, between two and three years ago, 

 cut a wide drain along the front of the border, the lower end of which was made to 

 open into a pine-stove, which is on a lower level than the vinery; and all the old 

 cross-drains under the border wei-e let into the front drain, which was carried for- 

 ward into a house on a higher level, so that a current of warm air from the pine- 

 stove was made to pass continually along the front of the border, and by shutting 

 the top end of the drain at intervals it was made to circulate also among the 



