PLANTING AND CULTURAL SUGGESTIONS 
Irises are one of the easiest of all perennials to grow 
and give much satisfaction with the minimum of care, for 
they can be entirely neglected and still thrive in the 
garden. However, to obtain the best results the following 
cultural hints should be observed. 
Select a sunny, well-drained location for planting. 
Irises will grow in semi-shade but will bloom more freely 
if they have sun at least half the day. Where the soil is 
heavy and the drainage is poor, it is best to plant on 
ridges, for the one thing irises cannot survive is water 
standing around them. Provide excellent drainage even if 
it is necessary to add sand or gravel to the soil. 
If your garden is new, probably no fertilizer will be 
necessary, but where the soil is poor some commercial 
fertilizer, such as Vigoro, should be used. Bone meal is 
also an excellent fertilizer and can be dug into the soil 
between the plants when it is thought desirable to supply 
more food. Be careful in using manure. It should never be 
used in heavy soils and if used at all, it must be well- 
rotted and extreme care must be exercised to see that the 
manure does not come into actual contact with the rhizomes 
because it is likely to cause rot. Feeding once in the fall 
and once or twice in the spring should be adequate. 
To give good bloom, irises should have room to grow. 
Place the plants twelve to eighteen inches apart and do 
not plant too deep—just cover the rhizomes. They usually 
become crowded in three or four years and should then 
be lifted, divided and reset. This is always a good time 
to refertilize the soil. Some of the newer, more vigorous 
varieties may grow so rapidly that they will need to be 
divided at the end of two years. 
Water well after planting and then keep moderately 
moist until well established and growing. If necessary, 
established plantings of irises may be left all summer with¬ 
out water, but an occasional soaking will give more 
increase and better blooms in the spring. Keep moderately 
moist before and d uring the blooming season to produce 
the best flowers. Do not water during extreme hot weather. 
Cultivate lightly after watering to prevent the soil from 
caking. 
Where it is possible to keep the plants watered until 
they become established, the month of June is perhaps 
the best time to plant. If watering is not possible, the fall 
months are best. It is only natural_that rhizomes shipped in 
the fall after they have had three or four months 
to develop following the blooming season will 
be larger than those shipped in June. However, 
the results obtained by planting the smaller 
rhizomes in June and getting the summer growth 
in your own garden are in some cases superior 
to those obtained from later planting. If pos¬ 
sible avoid planting during extreme hot weather. 
PESTS AND DISEASES 
Snails an d Slugs. The most common pests found on irises 
are snails and slugs. These can be easily controlled with 
the new snail poison now on the market. In this connection 
it is always advisable to keep the dead leaves and trash 
removed from around your iris plants. 
White Fly. I n some sections of the country this small 
insect is occasionally found on irises especially when 
planted in the shade. The tiny white flies lay their eggs on 
the iris leaves, and while they in no way injure the growth 
of the plants, they are easily controlled with any nicotine 
spray. 
Leaf Spot. This is a fungus which sometimes develops 
on iris leaves and causes the ends to turn brown. The 
spores multiply and often spread rapidly during damp 
spring weather. To check this fungus, spray with a lime- 
sulphur spray to which a little soap has been added as a 
spreader. This spray may be obtained at any good seed 
store. 
Rhizome Rot. This is caused by lack of drainage or by 
too much rain or watering, followed by warm weather. 
Usually the disease does not spread much and nature will 
check it. Often only part of the clump will perish. White 
maggots may be found in the diseased portion, but they 
are not the cause. 
When rhizome rot occurs, scrape away the soil and 
expose the entire rhizome to the sun and air. Remove the 
rotted part and allow the rhizome to dry several days 
before replacing the soil. Do not allow your iris rhizomes 
to be covered too deep. If you are bothered with rot, it is 
better to leave the tops of the rhizomes exposed at all times. 
MILLIKEN IRIS GARDENS 
970 NEW YORK AVENUE, PASADENA, CALIFORNIA 
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