NOVEMBER, 



BOTTOM HEAT. 



341 



Our concluding remarks will have reference to the application of bottom 

 heat to the culture of exutic plants, more especially with the view of 

 seeing how lar it can be recommended as a means of inducing tender 

 plants to bloom in the open air during summer with this assistance, as 

 well as lor employing it for heating borders in wliich we consider many 

 fine plants now ditticult to grow and bloom might be made to thrive and 

 produce their flowers ireely. 



In a former paper 1 gave the results of an experiment with some 

 stove plants which were provided with bottom heat and left to bloom 

 in the open air. Witnessing ihis fact has induced me to pay closer 

 attention to the subject ever since. 



In most gardens where stove plants are grown, many surplus plants 

 are to be met with in the spring, which from one cause or other become 

 unfit longer for pot culture. If a bed could be arranged in a shel- 

 tered place, but open to the south, so as to contain a depth of some 12 

 or 15 inches of soil of a sandy nature, and a pipe could be carried un- 

 derneath the soil, so as to give a uniform heat ot 70° or thereabouts, and 

 all the surplus stove plants were transferred to the open border towards 

 the end of May (having kept them previously dry and cool so as to 

 keep in check any active growth), and giving them the protection of 

 spare lights placed over a temporary frame for a few weeks by night 

 and during wet cold days, I have no doubt that they would start 

 into vigorous growth, and tlower as freely during August and September 

 as those did under my experiment. When the weather becaaie settled, 

 and the plants had become inured to their quarters, the framing, &c., 

 should be removed that the plants were growing in, and the group 

 would present a perfectly natural appearance. Care must, however, 

 be taken to prevent their growing too fast, as some of them would be 

 inclined to do, and a short supply of water, and a spade run round their 

 roots now and then, would give a wholesome check to their luxuriance, 

 and induce them to bloom. Clerodendrons, Vincas, Justicias, Cannas, 

 Allamandas, Jasminums, Achimenes, Ixoras, and many similar plants 

 would bloom profusely, and well repay the little extra trouble of culti- 

 vation ; and I don"t know a finer object than a group of such plants 

 blooming in the open air would present in August and September. 



But the above experiment is but one of several ways by which the 

 beauty ot our gardens might be increased by inducing exotics to bloom 

 out of doors. Conservative walls have long been tried with success for 

 greenhouse plants, and for which we have to thank Sir Joseph Paxton, 

 who first introduced them to the princely gard'-n at Chatsworth. On 

 these many things previously reputed tender thrive prodigiously, and 

 bloom with such profusion that no comparison can be made between 

 plants so situate and the same kinds growing in pots under glass. Now 

 we think by tlie introduction of hot-water pipes underneath the border 

 of a south wall, and with the same |)rotection as is usually given green- 

 house plants during winter, most of our stove climbers would grow and 

 fiovver freely ; and surely it would be worth something to see Ipomceas 



