CHICAGO American Buh Company NEW YORK 
TEMPERATURE 
The night temperature must be at least 60°F. when 
short day conditions are started to form flower buds. 
In fact, a 62°F. night temperature is somewhat safer 
since there is considerable variation of the temperature 
in different parts of the greenhouse. In case the air 
around one or more beds is slightly cooler, the plants 
can be covered with black cloth and a heating pipe 
placed underneath to insure a high enough tempera- 
ture. If it is possible to lower the temperature to 55° 
to 58°F. after the buds are clearly visible, quality will 
be improved though maturity will be slightly delayed. 
In summer there will often be a delay in develop- 
ment caused by excessive heat under the black cloth. 
Some of this can be prevented by waiting until 7 P.M. 
before putting on the cloth and then removing it at 
the customary time in the morning. Fans are also help- 
ful in bringing in cooler air under the cloth. When the 
night temperature reaches 85° or 90°F. under the 
cloth for as little as one hour, delay can be expected. 
When the 13 and 14-week varieties are used, delay of 
flowering is common at a night temperature of 65°F. 
Pink, bronze, and red varieties generally fade quite 
badly if flowered from June to September and except 
for certain varieties their use at this period is not rec- 
ommended. Burning of the petals of some of the soft 
varieties can be prevented in hot, bright weather by 
placing cheesecloth about 2 feet above the flowers. 
SPACING 
The more space a stem is given, the larger and 
heavier will be the spray or the size of the flower. 
Overdoing space will result in such large pompon 
sprays that retailers may not buy them. Therefore, a 
6 x 4 inch spacing for spray types and 6 x 5 inch spacing 
for standards is suggested when the no pinch schedule 
is to be used. It is possible that even closer spacing 
can be used to advantage; much depends on how much 
sunlight the plants receive and the market preference. 
GENERAL SUGGESTIONS 
The growth of the plants must never be checked if 
a schedule is to be followed. Therefore, thorough at- 
tention must be given to soil preparation, fertilizers, 
watering, etc., so that there will be no delay in growth. 
The general cultural practices of disbudding, cutting, 
etc., are the same as with chrysanthemums flowered at 
their normal time. 
Potted Chrysanthemums 
Improved cultural practices have revived the popu- 
larity of potted mums and today they are available on 
a year around basis. More than anything else, their 
good keeping quality has contributed to their success. 
Today’s methods are centered around rapid, un- 
checked growth and 90 to 100 days is about the average 
length of time for production of quality pot mums. 
SOIL 
Rapid development of the plants can only be obtained 
if the soil mixture is ideal. Incorporating 1/4 to 1/3 
rotted manure or peat moss or a combination of the 
two is about the best method of getting a soil that is 
porous and well drained yet will hold adequate mois- 
ture. Steam sterilization is the best method of com- 
batting insect pests, diseases, weeds, and weed seeds. 
FERTILIZERS 
As soon as the roots begin to develop along the pot 
wall, it is time to begin fertilizing. This will be about 
a week after potting if conditions are right. Because 
the plants will be watered so frequently, the use of a 
complete fertilizer every 7 days is advised. Whether 
the fertilizer is applied dry or liquid makes no differ- 
ence but liquid applications are much faster. Fertiliza- 
tion should continue until the plants are ready for sale. 
WATERING 
After the plants become established and considerable 
foliage develops, they will require frequent watering. 
In summer it may be necessary to water them three 
times a day depending upon the temperature and size 
of the plants. This is so because the plants are usually 
grown with no shade on the glass. When the flowers 
are opening and the plants are almost mature, over- 
watering will kill the roots and it is at this time that 
good judgment be used in applying water. 
TEMPERATURE 
Uniform formation of flower buds is best obtained 
by keeping the night temperature at 65°F. when short 
days are started. After buds are visible the tempera- 
ture can be lowered to 60° to 62°F. Too low a night 
temperature causes uneven formation of flower buds 
or blindness on some shoots. 
In very hot summer weather delay in development is 
common. At this time of year yellow and white va- 
rieties should be grown because most pink, red, or 
bronze types fade badly. 
DISBUDDING 
The greatest demand is for the large sized flowers, 
therefore, each stem should be disbudded to one flower. 
Don’t start disbudding until most of the shoots have 
buds large enough to handle easily; otherwise if you 
disbud only a stem or two at a time, the shoots dis- 
budded first will flower too far ahead of those dis- 
budded later. 
PINCHING 
Although the single pinch system is universally used, 
occasionally no pinch is employed and for very large 
plants the double pinch system is best. 
No pinch — the main advantage is larger flowers on 
varieties like the Indianapolis group. From 6 to 9 cut- 
tings are placed in a 6-inch azalea pot and short days 
are started about 7 days after potting. 
Single pinch — this is used by most growers because 
it is fast and the size of the specimens will satisfy most 
demands. Five or 6 cuttings are placed in a 6-inch 
azalea pot and the plants are pinched 7 days after pot- 
ting. Pinch relatively soft—if pinched too low, there 
will be fewer breaks. The plants should be shaded the 
same day they are pinched. In very dark weather the 
plants may be too short and this can be overcome by 
lighting for 7 days after pinching, then starting short 
day treatment. 
