152 ALPINE PLANTS 
ground, the growth may be compared to that of the German 
or flag Iris on a diminutive scale; the flowers, however, 
are not reduced in the same proportion as the stems and 
foliage. Quite a number of named garden varieties of 
I. pumila are in cultivation, several of them having effec- 
tive combinations of blue, purple and lavender in their 
colouring. There are, however, yellows, and white grounds 
with varied pencillings and feathering of either blue or 
brown. The plants grow from rhizomes which should 
be kept at the ground level when planting, and the best 
time to divide and replant is within two or three weeks 
of their passing out of bloom. For a month or so after 
planting it will be necessary to pay some attention to 
watering, but after the plants have made good root and 
become well settled in their new quarters they will be 
well able to look after themselves. Iris pumila in such 
varieties as bicolor, lutea maculata, versicolor, aquiloba 
and cerulea make excellent subjects for the alpine house, 
planted in pans, and moderately fed with weak liquid 
manure while the flower buds are developing. Those who 
wish to have a more extensive selection of irises in their 
alpine collection will find excellent material either for the 
rockery, the alpine bed, or the alpine house in I. cristata, 
with blue and lilac blossoms veined with golden yellow ; 
I. Douglasiana, rich violet; and I. Korolkowi, a very lovely 
flower with brown netting over a white ground. The 
bulbous I. reticulata should certainly not be omitted, 
the bulbs being planted in autumn, choosing positions 
where jutting stones will afford shelter for the precocious 
little blossoms. In due time the rather more exacting 
