HOW T0 GROW IRIS 
Twelve Easy Rules to Follow for Beautiful Blooms 
TO THE BEGINNER. Iris are one of the easiest perennials to 
grow. ‘They survive with less care and reward you with fine 
bloom with a minimum of attention. These few suggestions 
are all simple and proper care is very easy. Treat yourself to 
some of the finer Iris that have been developed recently. 
SOIL PREPARATION. Work soil well to a depth of 10 to 12 
inches. If soil is heavy, incorporate sand so moisture perco- 
lates out quickly. The soil should not be acid. If it is, apply 
lime, otherwise no lime is recommended. 
FERTILIZATION. Iris will thrive without feeding but will re- 
spond to its application. In the matter of fertilizers, garden 
sense should be used in liberal quantity. A nice garden soil 
will grow fine Iris. Use care not to get nitrogenous materials 
on or near the roots, rot may start. An excessively heavy 
nitrogenous feeding will give very lush growth which is more 
susceptible to rot. In the preparation of your new Iris bed, 
spade in a good application of compost below the roots. Well 
processed compost is ideal. Then an application of a well 
balanced fertilizer applied as a top dressing dusted around 
and in between the plants in early spring or very late fall is 
desirable. Steamed bone meal and super-phosphate are fine 
top dressing materials. The compost furnishes humus and 
valuable soil organisms. We have found the yearly spring 
application of gypsum, just as growth starts, has always been 
helpful as an antidote for Iris troubles; it also helps as a soil 
conditioner. It is easy to overdo Iris fertilizing, but undesir- 
able to omit feeding entirely. 
CULTIVATING. Do it shallowly. Iris feeding roots are very near 
the surface. Keep your Iris free of weeds and do not allow 
neighboring plants to encroach upon them. Remember, they 
should have sunlight right down to the rhizome. Remove the 
outer leaves as they begin to brown. At all times keep litter, 
old Iris leaves, grasses, etc., away from the rhizomes. Clean 
cultivation is the finest precaution for Iris troubles. 
WHEN TO PLANT. For best results plant July through Sep- 
tember. Early planting establishes the new Iris plants before 
winter. ‘This is the time to reset clumps of Iris that are 
crowded, generally clumps 3 to 4 years old. In the extreme 
heat of the South, it is more advisable to plant after the ex- 
tremes of summer heat are over—September is recommended. 
WHERE TO PLANT. The ideal location for your Ivis is a sunny, 
well drained position. Sunshine, at a minimum half days; Ivis 
will not do well in the deep shade. No water should stand in 
your Iris beds. Raise beds slightly above the level of your 
garden paths if necessary. 
DEPTH TO PLANT. Place your rhizomes just below the surface 
of the ground with the roots well spread out underneath so 
the rhizome is within reach of the warmth of the sun’s rays 
while the roots beneath are in moist (not soggy) soil. Be sure 
to firm the soil tightly around each rhizome when planting. 
Follow ordinary good garden practice of watering and setting 
soil on newly set plants, of course. 
WATERING. Depends on location. Newly set plants need mois- 
ture so they can grow a new root system. They appreciate 
this attention. Water at fairly long intervals in dry weather. 
Established plants do not require watering except in very arid 
parts of the country. ‘The common mistake is to give the Iris 
too much water. At times of excessive heat newly set plants 
can be shaded by an upright shingle or some such protection 
cutting off the direct rays of the sun for a few days. 
Page 46 
GENERAL GARDEN CARE. We prefer to cultivate shallowly 
after each rain when the ground has dried sufficiently for 
proper tilth. As the Iris grow, the outside foliage becomes 
limp. We remove these outside leaves every so often. Particu- 
larly about two weeks after blooming time. We do not trim 
the Iris foliage on established plants except to cut off some 
leaf spot should that show up. Blooms stems are cut level 
with the ground after blooming on a dry day so the cut heals 
quickly. 
SHOULD OLD CLUMPS BE THINNED. Yes, after they become 
crowded, about every four years. Dig up clumps, remove and 
discard the old center divisions that have blossomed and re- 
plant the fresh, largest foliage fans after the soil has been 
renovated. If you wish, the old center rhizomes and smaller 
fans may be grown in a nursery row a year, cut apart to single 
or double units. 
WINTER PROTECTION. We strongly advocate protective win- 
ter covering, particularly in the most northern sections. A light 
covering of marsh hay, straw, or some like weed-free litter is 
highly advised. New set plants in particular must be pro- 
tected as a preventative to the injury caused by freezing and 
thawing. Remove covering when spring growth begins. 
LEAF SPOT. Easily recognized from characteristic brown spots 
on foliage. Treatment, remove and burn diseased portions; 
spray or dust with Bordeaux or Fermate at strength recom- 
mended for roses. In case of sprays use a good sticker so spray 
adheres to foliage. 
IRIS BORER. For this pest we recommend Gray’s Iris Borer 
Eradicator. This is obtainable from Gray, Inc., 7217 Division 
St., River Forest, Ill. $1.50 for a pint bottle. This is the life 
cycle of the Iris borer: in September and October a moth ap- 
pears which lays eggs. In April or May these eggs become 
minute larvae and these tiny worms crawl upward on the Iris 
leaves feeding and leaving the edges of the leaves “notched.” 
From the leaf they work into the rhizome and after eating on 
it they tunnel out into the soil and become pupae. Then in 
fall this pupae moves up to the surface and becomes a moth 
and the cycle is completed. 
