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Ferns require winter weather of a very decided kind, 

 such as we experienced daring the winter ending May, 1917. 

 Then we had a mild autumn followed by protracted spells 

 of frost, with an average night temperature of 25 degrees 

 Fahrenheit. These conditions prevailed until towards the 

 end of May. Asplenium marinum and Ad. capillus- 

 Veneris in cold houses were mostly killed, but among ferns 

 in the open ground, such as Athy r iums, lar ge Pohjsiichums, 

 Lastreas and Osrnundas, the deaths were nil. Small late 

 transplanted plants of shallow rooting varieties of P. angu- 

 lare died to the extent of perhaps 5 per cent, in the open 

 ground, but under glass all were uninjured. 



If we could have the weather to order, that best suited 

 to ferns would be : Autumn with occasional slight frosts 

 such as we are now experiencing (1917), then a cold but 

 frostless January, then a moderate fall of snow with cold 

 frosty subarctic weather until mid May. Such conditions 

 are conducive to thorough rest, with that refreshing dream- 

 less slumber which is so essential to a vigorous and uniform 

 start in spring. 



After mild winters the ferns will often begin to move 

 during the second week in April, and the first crop of fronds, 

 which ought to be the best, is bound to suffer from the 

 effects of the frosts which will inevitably occur a month 

 later. If on the other hand the weather in March and 

 April is very mixed, the crowns are liable to issue their 

 contents in serial fashion instead of all the fronds marching 

 together. 



Ferns cannot be disturbed (hiring March without hasten- 

 ing the start. This is a matter of no consequence provided 

 we get a frostless May. Unfortunately, however, May has 

 rather a bad character, and we rarely get a frostless May. 

 For this reason autumn planting is most desirable, whilst 



