
CULTURAL POINTERS Wi hort 
Gilat P. ointers 
SOIL 
Chrysanthemums will grow well in a wide range of soil types but a fibrous silt loam is preferred. 
Blue grass sod to which rotted manure has been added plus an application of super phosphate has 
given excellent results. A soil that does not remain too open is preferred for this crop. 
Many growers plant chrysanthemums in old soil without sterilizing and expect good results. Many 
diseases and too much fertility are often found in old soil. Verticillium wilt (Seidewitz disease) is 
carried over in the old soil. If cultured cuttings are planted into old soil many varieties will become 
affected with wilt. The only reliable method is to sterilize with steam so that the soil is heated to 180 
to 200 degrees F. for at least one hour. If the soil is high in nitrate nitrogen we suggest you apply 
two inches of alfalfa or red clover hay into the soil in place of manure before sterilizing. This coarse 
fiber will reduce the nitrates and also adds humus to the soil. After sterilizing leach the soil with 
large quantities of water to reduce the available nutrients. 
Where steam sterilization is not available such as in cloth houses we suggest that you sterilize with 
formaldehyde liquid. Dilute one gallon of formaldehyde to 50 gallons of water and add this solution 
at the rate of 2 gallon per square foot of bed area. Allow the fumes to leave the soil before plant- 
ing. Soil should be well tilled before applying liquid. 
Still another chemical which has proven its worth is Larvacide. This material must be used when the 
greenhouses are empty to avoid injury to adjoining crops. This gas is applied in liquid form with a 
special applicator so that 2 to 3 c.c. are applied at 10 inch centers. The soil should be moist before 
applying. A good suitable covering should be placed over the treated soil to keep the gas in the soil 
for at least 48 hours, although a water seal applied 2 to 3 times every 24 hours will suffice. The soil 
temperature should be at least 60 degrees or higher. When used properly you can expect favor- 
able control of insects, diseases and weed seeds. 
Evidence shows that the soil reaction should be slightly acid pH 6.5, although in many instances a 
neutral medium does very well. If your soil tests slightly alkaline apply 2 to one pound of agricul- 
tural sulfur per 100 sqaure feet of area. However, if your soil is acid apply 3 to 5 pounds of agri- 
cultural ground limestone per 100 square feet of area. 
Proper drainage and proper aeration of the soil are very vital to good growth. Many times improp- 
er drainage of the bench or bed is the reason for a poor crop. No wet spots should ever be pres- 
ent. Soil drainage may be improved by the addition of various materials. Any coarse organic ma- 
~ terial such as manure, alfalfa hay or clover hay applied at the rate not to exceed one fourth the 
volume will separate the soil particles sufficiently to increase pore space. Heavy applications of sand 
to a soil have not always proven of value to a chrysanthemum crop. Aeration may also be increased 
by proper cultivation of the soil. Frequent scratchings are recommended during the early growth of 
the crop. 

Thrip Injury Mite Injury Plant on Left Normal, 
Right Infected 
