268 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



nicotine compounds on the market. Red spider may be trouble- 

 some, but it is generally a sign of neglect if it is allowed to get bad. 



Black spot is a very bad disease if it appears at all, and certain 

 varieties are more subject to it than others, but if it is remembered 

 that a close, confined atmosphere, with a rather high temperature 

 during the day and a close atmosphere and low temperature at night, 

 will almost certainly cause it to appear, it will be easy to avoid it 

 by avoiding the conditions necessary for its appearance. If a bad 

 attack should come about, really the best thing to do is to throw the 

 plants away, or anyhow to give up all idea of saving that particular 

 crop, and to try to get some growth on for the next crop. 



Ample ventilation,- a fairly warm temperature, and cutting off of 

 all diseased shoots will probably be sufficient to get rid of the disease 

 if the treatment afterwards is correct ; but, as I have already said, if 

 the attack is bad it is almost hopeless to expect to save the current 

 crop of flowers. 



After the plants have flowered and the flowers are cut off, they 

 will require to be kept well syringed and to be fed up again to induce 

 the second crop of flowers, and the treatment is very similar to that 

 already detailed. The only thing to remember is that the days are now 

 longer and probably much warmer under glass, and that the plants 

 will require rather more watering and syringing. This is a usual time 

 to get an attack of red spider, and care should be taken to check 

 it immediately it appears. Of course the soil will require stirring 

 up slightly now and again during the growing period, say about once 

 a month or six weeks, but not very deeply — only just enough to loosen 

 the top and to get rid of any weeds. The second crop will be in 

 flower about April, and the third about the end of June. After this 

 we usually stand our plants outdoors in the full sun on a well-drained 

 piece of ground, and let them stay there until it is time to bring them 

 in again by October. During the summer they will require a good 

 deal of water, but we do not plunge them up in ashes or anything, 

 as we find they ripen the wood better if left standing open. It is 

 rather more trouble, but the results seem to us to repay it. 



If it is not possible to get the roses into the greenhouse as early 

 as October, they can be brought in at any time up to the end of 

 January, but after November they are better pruned as soon as 

 possible and left to come along slowly, though it is not advisable to 

 prune or top-dress them if the soil is too wet. They should always 

 be left to get moderately dry before doing anything to them. 



We may thus summarize our methods : Roses under glass require 

 a well-ventilated house, with plenty of ventilation at the start ; a 

 temperature of about 55° ; not too much watering during the winter, 

 though plenty during the spring and summer, and the same with 

 syringing ; a fair amount of manure, which is easily given to them in 

 the water, and special attention to mildew, and in a lesser degree 

 to green fly and red spider. 



